/*----------------------------------------------------------------------------/
/  FatFs - Generic FAT Filesystem Module  R0.15 w/patch3                      /
/-----------------------------------------------------------------------------/
/
/ Copyright (C) 2022, ChaN, all right reserved.
/
/ FatFs module is an open source software. Redistribution and use of FatFs in
/ source and binary forms, with or without modification, are permitted provided
/ that the following condition is met:
/
/ 1. Redistributions of source code must retain the above copyright notice,
/    this condition and the following disclaimer.
/
/ This software is provided by the copyright holder and contributors "AS IS"
/ and any warranties related to this software are DISCLAIMED.
/ The copyright owner or contributors be NOT LIABLE for any damages caused
/ by use of this software.
/
/----------------------------------------------------------------------------*/

#include "ff.h"     /* Declarations of FatFs API */
#include "diskio.h" /* Declarations of device I/O functions */

/*--------------------------------------------------------------------------

   Module Private Definitions

---------------------------------------------------------------------------*/

#if FF_DEFINED != 80286 /* Revision ID */
#  error Wrong include file (ff.h).
#endif

/* Limits and boundaries */
#define MAX_DIR    0x200000   /* Max size of FAT directory */
#define MAX_DIR_EX 0x10000000 /* Max size of exFAT directory */
#define MAX_FAT12                                                                                  \
  0xFF5 /* Max FAT12 clusters (differs from specs, but right for real DOS/Windows behavior) */
#define MAX_FAT16                                                                                  \
  0xFFF5 /* Max FAT16 clusters (differs from specs, but right for real DOS/Windows behavior) */
#define MAX_FAT32 0x0FFFFFF5 /* Max FAT32 clusters (not specified, practical limit) */
#define MAX_EXFAT 0x7FFFFFFD /* Max exFAT clusters (differs from specs, implementation limit) */

/* Character code support macros */
#define IsUpper(c)      ((c) >= 'A' && (c) <= 'Z')
#define IsLower(c)      ((c) >= 'a' && (c) <= 'z')
#define IsDigit(c)      ((c) >= '0' && (c) <= '9')
#define IsSeparator(c)  ((c) == '/' || (c) == '\\')
#define IsTerminator(c) ((uint)(c) < (FF_USE_LFN ? ' ' : '!'))
#define IsSurrogate(c)  ((c) >= 0xD800 && (c) <= 0xDFFF)
#define IsSurrogateH(c) ((c) >= 0xD800 && (c) <= 0xDBFF)
#define IsSurrogateL(c) ((c) >= 0xDC00 && (c) <= 0xDFFF)

/* Additional file access control and file status flags for internal use */
#define FA_SEEKEND  0x20 /* Seek to end of the file on file open */
#define FA_MODIFIED 0x40 /* File has been modified */
#define FA_DIRTY    0x80 /* FIL.buf[] needs to be written-back */

/* Additional file attribute bits for internal use */
#define AM_VOL   0x08 /* Volume label */
#define AM_LFN   0x0F /* LFN entry */
#define AM_MASK  0x3F /* Mask of defined bits in FAT */
#define AM_MASKX 0x37 /* Mask of defined bits in exFAT */

/* Name status flags in fn[11] */
#define NSFLAG    11   /* Index of the name status byte */
#define NS_LOSS   0x01 /* Out of 8.3 format */
#define NS_LFN    0x02 /* Force to create LFN entry */
#define NS_LAST   0x04 /* Last segment */
#define NS_BODY   0x08 /* Lower case flag (body) */
#define NS_EXT    0x10 /* Lower case flag (ext) */
#define NS_DOT    0x20 /* Dot entry */
#define NS_NOLFN  0x40 /* Do not find LFN */
#define NS_NONAME 0x80 /* Not followed */

/* exFAT directory entry types */
#define ET_BITMAP   0x81 /* Allocation bitmap */
#define ET_UPCASE   0x82 /* Up-case table */
#define ET_VLABEL   0x83 /* Volume label */
#define ET_FILEDIR  0x85 /* File and directory */
#define ET_STREAM   0xC0 /* Stream extension */
#define ET_FILENAME 0xC1 /* Name extension */

/* FatFs refers the FAT structure as simple byte array instead of structure member
/ because the C structure is not binary compatible between different platforms */

#define BS_JmpBoot     0   /* x86 jump instruction (3-byte) */
#define BS_OEMName     3   /* OEM name (8-byte) */
#define BPB_BytsPerSec 11  /* Sector size [byte] (u16) */
#define BPB_SecPerClus 13  /* Cluster size [sector] (byte) */
#define BPB_RsvdSecCnt 14  /* Size of reserved area [sector] (u16) */
#define BPB_NumFATs    16  /* Number of FATs (byte) */
#define BPB_RootEntCnt 17  /* Size of root directory area for FAT [entry] (u16) */
#define BPB_TotSec16   19  /* Volume size (16-bit) [sector] (u16) */
#define BPB_Media      21  /* Media descriptor byte (byte) */
#define BPB_FATSz16    22  /* FAT size (16-bit) [sector] (u16) */
#define BPB_SecPerTrk  24  /* Number of sectors per track for int13h [sector] (u16) */
#define BPB_NumHeads   26  /* Number of heads for int13h (u16) */
#define BPB_HiddSec    28  /* Volume offset from top of the drive (u32) */
#define BPB_TotSec32   32  /* Volume size (32-bit) [sector] (u32) */
#define BS_DrvNum      36  /* Physical drive number for int13h (byte) */
#define BS_NTres       37  /* WindowsNT error flag (byte) */
#define BS_BootSig     38  /* Extended boot signature (byte) */
#define BS_VolID       39  /* Volume serial number (u32) */
#define BS_VolLab      43  /* Volume label string (8-byte) */
#define BS_FilSysType  54  /* Filesystem type string (8-byte) */
#define BS_BootCode    62  /* Boot code (448-byte) */
#define BS_55AA        510 /* Signature word (u16) */

#define BPB_FATSz32     36 /* FAT32: FAT size [sector] (u32) */
#define BPB_ExtFlags32  40 /* FAT32: Extended flags (u16) */
#define BPB_FSVer32     42 /* FAT32: Filesystem version (u16) */
#define BPB_RootClus32  44 /* FAT32: Root directory cluster (u32) */
#define BPB_FSInfo32    48 /* FAT32: Offset of FSINFO sector (u16) */
#define BPB_BkBootSec32 50 /* FAT32: Offset of backup boot sector (u16) */
#define BS_DrvNum32     64 /* FAT32: Physical drive number for int13h (byte) */
#define BS_NTres32      65 /* FAT32: Error flag (byte) */
#define BS_BootSig32    66 /* FAT32: Extended boot signature (byte) */
#define BS_VolID32      67 /* FAT32: Volume serial number (u32) */
#define BS_VolLab32     71 /* FAT32: Volume label string (8-byte) */
#define BS_FilSysType32 82 /* FAT32: Filesystem type string (8-byte) */
#define BS_BootCode32   90 /* FAT32: Boot code (420-byte) */

#define BPB_ZeroedEx     11  /* exFAT: MBZ field (53-byte) */
#define BPB_VolOfsEx     64  /* exFAT: Volume offset from top of the drive [sector] (u64) */
#define BPB_TotSecEx     72  /* exFAT: Volume size [sector] (u64) */
#define BPB_FatOfsEx     80  /* exFAT: FAT offset from top of the volume [sector] (u32) */
#define BPB_FatSzEx      84  /* exFAT: FAT size [sector] (u32) */
#define BPB_DataOfsEx    88  /* exFAT: Data offset from top of the volume [sector] (u32) */
#define BPB_NumClusEx    92  /* exFAT: Number of clusters (u32) */
#define BPB_RootClusEx   96  /* exFAT: Root directory start cluster (u32) */
#define BPB_VolIDEx      100 /* exFAT: Volume serial number (u32) */
#define BPB_FSVerEx      104 /* exFAT: Filesystem version (u16) */
#define BPB_VolFlagEx    106 /* exFAT: Volume flags (u16) */
#define BPB_BytsPerSecEx 108 /* exFAT: Log2 of sector size in unit of byte (byte) */
#define BPB_SecPerClusEx 109 /* exFAT: Log2 of cluster size in unit of sector (byte) */
#define BPB_NumFATsEx    110 /* exFAT: Number of FATs (byte) */
#define BPB_DrvNumEx     111 /* exFAT: Physical drive number for int13h (byte) */
#define BPB_PercInUseEx  112 /* exFAT: Percent in use (byte) */
#define BPB_RsvdEx       113 /* exFAT: Reserved (7-byte) */
#define BS_BootCodeEx    120 /* exFAT: Boot code (390-byte) */

#define DIR_Name           0  /* Short file name (11-byte) */
#define DIR_Attr           11 /* Attribute (byte) */
#define DIR_NTres          12 /* Lower case flag (byte) */
#define DIR_CrtTime10      13 /* Created time sub-second (byte) */
#define DIR_CrtTime        14 /* Created time (u32) */
#define DIR_LstAccDate     18 /* Last accessed date (u16) */
#define DIR_FstClusHI      20 /* Higher 16-bit of first cluster (u16) */
#define DIR_ModTime        22 /* Modified time (u32) */
#define DIR_FstClusLO      26 /* Lower 16-bit of first cluster (u16) */
#define DIR_FileSize       28 /* File size (u32) */
#define LDIR_Ord           0  /* LFN: LFN order and LLE flag (byte) */
#define LDIR_Attr          11 /* LFN: LFN attribute (byte) */
#define LDIR_Type          12 /* LFN: Entry type (byte) */
#define LDIR_Chksum        13 /* LFN: Checksum of the SFN (byte) */
#define LDIR_FstClusLO     26 /* LFN: MBZ field (u16) */
#define XDIR_Type          0  /* exFAT: Type of exFAT directory entry (byte) */
#define XDIR_NumLabel      1  /* exFAT: Number of volume label characters (byte) */
#define XDIR_Label         2  /* exFAT: Volume label (11-u16) */
#define XDIR_CaseSum       4  /* exFAT: Sum of case conversion table (u32) */
#define XDIR_NumSec        1  /* exFAT: Number of secondary entries (byte) */
#define XDIR_SetSum        2  /* exFAT: Sum of the set of directory entries (u16) */
#define XDIR_Attr          4  /* exFAT: File attribute (u16) */
#define XDIR_CrtTime       8  /* exFAT: Created time (u32) */
#define XDIR_ModTime       12 /* exFAT: Modified time (u32) */
#define XDIR_AccTime       16 /* exFAT: Last accessed time (u32) */
#define XDIR_CrtTime10     20 /* exFAT: Created time subsecond (byte) */
#define XDIR_ModTime10     21 /* exFAT: Modified time subsecond (byte) */
#define XDIR_CrtTZ         22 /* exFAT: Created timezone (byte) */
#define XDIR_ModTZ         23 /* exFAT: Modified timezone (byte) */
#define XDIR_AccTZ         24 /* exFAT: Last accessed timezone (byte) */
#define XDIR_GenFlags      33 /* exFAT: General secondary flags (byte) */
#define XDIR_NumName       35 /* exFAT: Number of file name characters (byte) */
#define XDIR_NameHash      36 /* exFAT: Hash of file name (u16) */
#define XDIR_ValidFileSize 40 /* exFAT: Valid file size (u64) */
#define XDIR_FstClus       52 /* exFAT: First cluster of the file data (u32) */
#define XDIR_FileSize      56 /* exFAT: File/Directory size (u64) */

#define SZDIRE 32   /* Size of a directory entry */
#define DDEM   0xE5 /* Deleted directory entry mark set to DIR_Name[0] */
#define RDDEM  0x05 /* Replacement of the character collides with DDEM */
#define LLEF   0x40 /* Last long entry flag in LDIR_Ord */

#define FSI_LeadSig    0   /* FAT32 FSI: Leading signature (u32) */
#define FSI_StrucSig   484 /* FAT32 FSI: Structure signature (u32) */
#define FSI_Free_Count 488 /* FAT32 FSI: Number of free clusters (u32) */
#define FSI_Nxt_Free   492 /* FAT32 FSI: Last allocated cluster (u32) */

#define MBR_Table  446 /* MBR: Offset of partition table in the MBR */
#define SZ_PTE     16  /* MBR: Size of a partition table entry */
#define PTE_Boot   0   /* MBR PTE: Boot indicator */
#define PTE_StHead 1   /* MBR PTE: Start head */
#define PTE_StSec  2   /* MBR PTE: Start sector */
#define PTE_StCyl  3   /* MBR PTE: Start cylinder */
#define PTE_System 4   /* MBR PTE: System ID */
#define PTE_EdHead 5   /* MBR PTE: End head */
#define PTE_EdSec  6   /* MBR PTE: End sector */
#define PTE_EdCyl  7   /* MBR PTE: End cylinder */
#define PTE_StLba  8   /* MBR PTE: Start in LBA */
#define PTE_SizLba 12  /* MBR PTE: Size in LBA */

#define GPTH_Sign    0   /* GPT HDR: Signature (8-byte) */
#define GPTH_Rev     8   /* GPT HDR: Revision (u32) */
#define GPTH_Size    12  /* GPT HDR: Header size (u32) */
#define GPTH_Bcc     16  /* GPT HDR: Header BCC (u32) */
#define GPTH_CurLba  24  /* GPT HDR: This header LBA (u64) */
#define GPTH_BakLba  32  /* GPT HDR: Another header LBA (u64) */
#define GPTH_FstLba  40  /* GPT HDR: First LBA for partition data (u64) */
#define GPTH_LstLba  48  /* GPT HDR: Last LBA for partition data (u64) */
#define GPTH_DskGuid 56  /* GPT HDR: Disk GUID (16-byte) */
#define GPTH_PtOfs   72  /* GPT HDR: Partition table LBA (u64) */
#define GPTH_PtNum   80  /* GPT HDR: Number of table entries (u32) */
#define GPTH_PteSize 84  /* GPT HDR: Size of table entry (u32) */
#define GPTH_PtBcc   88  /* GPT HDR: Partition table BCC (u32) */
#define SZ_GPTE      128 /* GPT PTE: Size of partition table entry */
#define GPTE_PtGuid  0   /* GPT PTE: Partition type GUID (16-byte) */
#define GPTE_UpGuid  16  /* GPT PTE: Partition unique GUID (16-byte) */
#define GPTE_FstLba  32  /* GPT PTE: First LBA of partition (u64) */
#define GPTE_LstLba  40  /* GPT PTE: Last LBA of partition (u64) */
#define GPTE_Flags   48  /* GPT PTE: Partition flags (u64) */
#define GPTE_Name    56  /* GPT PTE: Partition name */

/* Post process on fatal error in the file operations */
#define ABORT(fs, res)                                                                             \
  {                                                                                                \
    fp->err = (byte)(res);                                                                         \
    LEAVE_FF(fs, res);                                                                             \
  }

/* Re-entrancy related */
#if FF_FS_REENTRANT
#  if FF_USE_LFN == 1
#    error Static LFN work area cannot be used in thread-safe configuration
#  endif
#  define LEAVE_FF(fs, res)                                                                        \
    {                                                                                              \
      unlock_volume(fs, res);                                                                      \
      return res;                                                                                  \
    }
#else
#  define LEAVE_FF(fs, res) return res
#endif

/* Definitions of logical drive - physical location conversion */
#if FF_MULTI_PARTITION
#  define LD2PD(vol) VolToPart[vol].pd /* Get physical drive number */
#  define LD2PT(vol)                                                                               \
    VolToPart[vol].pt /* Get partition number (0:auto search, 1..:forced partition number) */
#else
#  define LD2PD(vol)                                                                               \
    (byte)(vol)        /* Each logical drive is associated with the same physical drive number */
#  define LD2PT(vol) 0 /* Auto partition search */
#endif

/* Definitions of sector size */
#if (FF_MAX_SS < FF_MIN_SS) ||                                                                     \
    (FF_MAX_SS != 512 && FF_MAX_SS != 1024 && FF_MAX_SS != 2048 && FF_MAX_SS != 4096) ||           \
    (FF_MIN_SS != 512 && FF_MIN_SS != 1024 && FF_MIN_SS != 2048 && FF_MIN_SS != 4096)
#  error Wrong sector size configuration
#endif
#if FF_MAX_SS == FF_MIN_SS
#  define SS(fs) ((uint)FF_MAX_SS) /* Fixed sector size */
#else
#  define SS(fs) ((fs)->ssize) /* Variable sector size */
#endif

/* Timestamp */
#if FF_FS_NORTC == 1
#  if FF_NORTC_YEAR < 1980 || FF_NORTC_YEAR > 2107 || FF_NORTC_MON < 1 || FF_NORTC_MON > 12 ||     \
      FF_NORTC_MDAY < 1 || FF_NORTC_MDAY > 31
#    error Invalid FF_FS_NORTC settings
#  endif
#  define GET_FATTIME()                                                                            \
    ((u32)(FF_NORTC_YEAR - 1980) << 25 | (u32)FF_NORTC_MON << 21 | (u32)FF_NORTC_MDAY << 16)
#else
#  define GET_FATTIME() get_fattime()
#endif

/* File lock controls */
#if FF_FS_LOCK
#  if FF_FS_READONLY
#    error FF_FS_LOCK must be 0 at read-only configuration
#  endif
typedef struct {
  FATFS *fs;  /* Object ID 1, volume (NULL:blank entry) */
  u32    clu; /* Object ID 2, containing directory (0:root) */
  u32    ofs; /* Object ID 3, offset in the directory */
  uint   ctr; /* Object open counter, 0:none, 0x01..0xFF:read mode open count, 0x100:write mode */
} FILESEM;
#endif

/* SBCS up-case tables (\x80-\xFF) */
#define TBL_CT437                                                                                  \
  {                                                                                                \
    0x80, 0x9A, 0x45, 0x41, 0x8E, 0x41, 0x8F, 0x80, 0x45, 0x45, 0x45, 0x49, 0x49, 0x49, 0x8E,      \
        0x8F, 0x90, 0x92, 0x92, 0x4F, 0x99, 0x4F, 0x55, 0x55, 0x59, 0x99, 0x9A, 0x9B, 0x9C, 0x9D,  \
        0x9E, 0x9F, 0x41, 0x49, 0x4F, 0x55, 0xA5, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8,  \
        0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT720                                                                                  \
  {                                                                                                \
    0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E,      \
        0x8F, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D,  \
        0x9E, 0x9F, 0xA0, 0xA1, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8,  \
        0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT737                                                                                  \
  {                                                                                                \
    0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E,      \
        0x8F, 0x90, 0x92, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85,  \
        0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E, 0x8F, 0x90, 0x91, 0xAA, 0x92, 0x93,  \
        0x94, 0x95, 0x96, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0x97, 0xEA, 0xEB, 0xEC, 0xE4, 0xED, 0xEE, 0xEF, 0xF5,  \
        0xF0, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT771                                                                                  \
  {                                                                                                \
    0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E,      \
        0x8F, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D,  \
        0x9E, 0x9F, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C,  \
        0x8D, 0x8E, 0x8F, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDC, 0xDE, 0xDE, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,  \
        0x99, 0x9A, 0x9B, 0x9C, 0x9D, 0x9E, 0x9F, 0xF0, 0xF0, 0xF2, 0xF2, 0xF4, 0xF4, 0xF6, 0xF6,  \
        0xF8, 0xF8, 0xFA, 0xFA, 0xFC, 0xFC, 0xFE, 0xFF                                             \
  }
#define TBL_CT775                                                                                  \
  {                                                                                                \
    0x80, 0x9A, 0x91, 0xA0, 0x8E, 0x95, 0x8F, 0x80, 0xAD, 0xED, 0x8A, 0x8A, 0xA1, 0x8D, 0x8E,      \
        0x8F, 0x90, 0x92, 0x92, 0xE2, 0x99, 0x95, 0x96, 0x97, 0x97, 0x99, 0x9A, 0x9D, 0x9C, 0x9D,  \
        0x9E, 0x9F, 0xA0, 0xA1, 0xE0, 0xA3, 0xA3, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xB5, 0xB6, 0xB7, 0xB8, 0xBD, 0xBE, 0xC6, 0xC7, 0xA5, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0xE0, 0xE1, 0xE2, 0xE3, 0xE5, 0xE5, 0xE6, 0xE3, 0xE8,  \
        0xE8, 0xEA, 0xEA, 0xEE, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT850                                                                                  \
  {                                                                                                \
    0x43, 0x55, 0x45, 0x41, 0x41, 0x41, 0x41, 0x43, 0x45, 0x45, 0x45, 0x49, 0x49, 0x49, 0x41,      \
        0x41, 0x45, 0x92, 0x92, 0x4F, 0x4F, 0x4F, 0x55, 0x55, 0x59, 0x4F, 0x55, 0x4F, 0x9C, 0x4F,  \
        0x9E, 0x9F, 0x41, 0x49, 0x4F, 0x55, 0xA5, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0x41, 0x41, 0x41, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0x41, 0x41, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD1, 0xD1, 0x45, 0x45, 0x45, 0x49, 0x49, 0x49, 0x49, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0x49, 0xDF, 0x4F, 0xE1, 0x4F, 0x4F, 0x4F, 0x4F, 0xE6, 0xE8, 0xE8,  \
        0x55, 0x55, 0x55, 0x59, 0x59, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT852                                                                                  \
  {                                                                                                \
    0x80, 0x9A, 0x90, 0xB6, 0x8E, 0xDE, 0x8F, 0x80, 0x9D, 0xD3, 0x8A, 0x8A, 0xD7, 0x8D, 0x8E,      \
        0x8F, 0x90, 0x91, 0x91, 0xE2, 0x99, 0x95, 0x95, 0x97, 0x97, 0x99, 0x9A, 0x9B, 0x9B, 0x9D,  \
        0x9E, 0xAC, 0xB5, 0xD6, 0xE0, 0xE9, 0xA4, 0xA4, 0xA6, 0xA6, 0xA8, 0xA8, 0xAA, 0x8D, 0xAC,  \
        0xB8, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBD, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC6, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD1, 0xD1, 0xD2, 0xD3, 0xD2, 0xD5, 0xD6, 0xD7, 0xB7, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0xE0, 0xE1, 0xE2, 0xE3, 0xE3, 0xD5, 0xE6, 0xE6, 0xE8,  \
        0xE9, 0xE8, 0xEB, 0xED, 0xED, 0xDD, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xEB, 0xFC, 0xFC, 0xFE, 0xFF                                             \
  }
#define TBL_CT855                                                                                  \
  {                                                                                                \
    0x81, 0x81, 0x83, 0x83, 0x85, 0x85, 0x87, 0x87, 0x89, 0x89, 0x8B, 0x8B, 0x8D, 0x8D, 0x8F,      \
        0x8F, 0x91, 0x91, 0x93, 0x93, 0x95, 0x95, 0x97, 0x97, 0x99, 0x99, 0x9B, 0x9B, 0x9D, 0x9D,  \
        0x9F, 0x9F, 0xA1, 0xA1, 0xA3, 0xA3, 0xA5, 0xA5, 0xA7, 0xA7, 0xA9, 0xA9, 0xAB, 0xAB, 0xAD,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB6, 0xB6, 0xB8, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBE, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC7, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD1, 0xD1, 0xD3, 0xD3, 0xD5, 0xD5, 0xD7, 0xD7, 0xDD, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xE0, 0xDF, 0xE0, 0xE2, 0xE2, 0xE4, 0xE4, 0xE6, 0xE6, 0xE8, 0xE8,  \
        0xEA, 0xEA, 0xEC, 0xEC, 0xEE, 0xEE, 0xEF, 0xF0, 0xF2, 0xF2, 0xF4, 0xF4, 0xF6, 0xF6, 0xF8,  \
        0xF8, 0xFA, 0xFA, 0xFC, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT857                                                                                  \
  {                                                                                                \
    0x80, 0x9A, 0x90, 0xB6, 0x8E, 0xB7, 0x8F, 0x80, 0xD2, 0xD3, 0xD4, 0xD8, 0xD7, 0x49, 0x8E,      \
        0x8F, 0x90, 0x92, 0x92, 0xE2, 0x99, 0xE3, 0xEA, 0xEB, 0x98, 0x99, 0x9A, 0x9D, 0x9C, 0x9D,  \
        0x9E, 0x9E, 0xB5, 0xD6, 0xE0, 0xE9, 0xA5, 0xA5, 0xA6, 0xA6, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC7, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0x49, 0xD6, 0xD7, 0xD8, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0xE0, 0xE1, 0xE2, 0xE3, 0xE5, 0xE5, 0xE6, 0xE7, 0xE8,  \
        0xE9, 0xEA, 0xEB, 0xDE, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT860                                                                                  \
  {                                                                                                \
    0x80, 0x9A, 0x90, 0x8F, 0x8E, 0x91, 0x86, 0x80, 0x89, 0x89, 0x92, 0x8B, 0x8C, 0x98, 0x8E,      \
        0x8F, 0x90, 0x91, 0x92, 0x8C, 0x99, 0xA9, 0x96, 0x9D, 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D,  \
        0x9E, 0x9F, 0x86, 0x8B, 0x9F, 0x96, 0xA5, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8,  \
        0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT861                                                                                  \
  {                                                                                                \
    0x80, 0x9A, 0x90, 0x41, 0x8E, 0x41, 0x8F, 0x80, 0x45, 0x45, 0x45, 0x8B, 0x8B, 0x8D, 0x8E,      \
        0x8F, 0x90, 0x92, 0x92, 0x4F, 0x99, 0x8D, 0x55, 0x97, 0x97, 0x99, 0x9A, 0x9D, 0x9C, 0x9D,  \
        0x9E, 0x9F, 0xA4, 0xA5, 0xA6, 0xA7, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8,  \
        0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT862                                                                                  \
  {                                                                                                \
    0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E,      \
        0x8F, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D,  \
        0x9E, 0x9F, 0x41, 0x49, 0x4F, 0x55, 0xA5, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8,  \
        0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT863                                                                                  \
  {                                                                                                \
    0x43, 0x55, 0x45, 0x41, 0x41, 0x41, 0x86, 0x43, 0x45, 0x45, 0x45, 0x49, 0x49, 0x8D, 0x41,      \
        0x8F, 0x45, 0x45, 0x45, 0x4F, 0x45, 0x49, 0x55, 0x55, 0x98, 0x4F, 0x55, 0x9B, 0x9C, 0x55,  \
        0x55, 0x9F, 0xA0, 0xA1, 0x4F, 0x55, 0xA4, 0xA5, 0xA6, 0xA7, 0x49, 0xA9, 0xAA, 0xAB, 0xAC,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8,  \
        0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT864                                                                                  \
  {                                                                                                \
    0x80, 0x9A, 0x45, 0x41, 0x8E, 0x41, 0x8F, 0x80, 0x45, 0x45, 0x45, 0x49, 0x49, 0x49, 0x8E,      \
        0x8F, 0x90, 0x92, 0x92, 0x4F, 0x99, 0x4F, 0x55, 0x55, 0x59, 0x99, 0x9A, 0x9B, 0x9C, 0x9D,  \
        0x9E, 0x9F, 0x41, 0x49, 0x4F, 0x55, 0xA5, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8,  \
        0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT865                                                                                  \
  {                                                                                                \
    0x80, 0x9A, 0x90, 0x41, 0x8E, 0x41, 0x8F, 0x80, 0x45, 0x45, 0x45, 0x49, 0x49, 0x49, 0x8E,      \
        0x8F, 0x90, 0x92, 0x92, 0x4F, 0x99, 0x4F, 0x55, 0x55, 0x59, 0x99, 0x9A, 0x9B, 0x9C, 0x9D,  \
        0x9E, 0x9F, 0x41, 0x49, 0x4F, 0x55, 0xA5, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8,  \
        0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT866                                                                                  \
  {                                                                                                \
    0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E,      \
        0x8F, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D,  \
        0x9E, 0x9F, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C,  \
        0x8D, 0x8E, 0x8F, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,  \
        0x99, 0x9A, 0x9B, 0x9C, 0x9D, 0x9E, 0x9F, 0xF0, 0xF0, 0xF2, 0xF2, 0xF4, 0xF4, 0xF6, 0xF6,  \
        0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF                                             \
  }
#define TBL_CT869                                                                                  \
  {                                                                                                \
    0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E,      \
        0x8F, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x86, 0x9C, 0x8D,  \
        0x8F, 0x90, 0x91, 0x90, 0x92, 0x95, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC,  \
        0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB,  \
        0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,  \
        0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xA4, 0xA5, 0xA6, 0xD9,  \
        0xDA, 0xDB, 0xDC, 0xA7, 0xA8, 0xDF, 0xA9, 0xAA, 0xAC, 0xAD, 0xB5, 0xB6, 0xB7, 0xB8, 0xBD,  \
        0xBE, 0xC6, 0xC7, 0xCF, 0xCF, 0xD0, 0xEF, 0xF0, 0xF1, 0xD1, 0xD2, 0xD3, 0xF5, 0xD4, 0xF7,  \
        0xF8, 0xF9, 0xD5, 0x96, 0x95, 0x98, 0xFE, 0xFF                                             \
  }

/* DBCS code range |----- 1st byte -----|  |----------- 2nd byte -----------| */
/*                  <------>    <------>    <------>    <------>    <------>  */
#define TBL_DC932                                                                                  \
  { 0x81, 0x9F, 0xE0, 0xFC, 0x40, 0x7E, 0x80, 0xFC, 0x00, 0x00 }
#define TBL_DC936                                                                                  \
  { 0x81, 0xFE, 0x00, 0x00, 0x40, 0x7E, 0x80, 0xFE, 0x00, 0x00 }
#define TBL_DC949                                                                                  \
  { 0x81, 0xFE, 0x00, 0x00, 0x41, 0x5A, 0x61, 0x7A, 0x81, 0xFE }
#define TBL_DC950                                                                                  \
  { 0x81, 0xFE, 0x00, 0x00, 0x40, 0x7E, 0xA1, 0xFE, 0x00, 0x00 }

/* Macros for table definitions */
#define MERGE_2STR(a, b) a##b
#define MKCVTBL(hd, cp)  MERGE_2STR(hd, cp)

/*--------------------------------------------------------------------------

   Module Private Work Area

---------------------------------------------------------------------------*/
/* Remark: Variables defined here without initial value shall be guaranteed
/  zero/null at start-up. If not, the linker option or start-up routine is
/  not compliance with C standard. */

/*--------------------------------*/
/* File/Volume controls           */
/*--------------------------------*/

#if FF_VOLUMES < 1 || FF_VOLUMES > 10
#  error Wrong FF_VOLUMES setting
#endif
static FATFS *FatFs[FF_VOLUMES]; /* Pointer to the filesystem objects (logical drives) */
static u16    Fsid;              /* Filesystem mount ID */

#if FF_FS_RPATH != 0
static byte CurrVol; /* Current drive set by f_chdrive() */
#endif

#if FF_FS_LOCK
static FILESEM Files[FF_FS_LOCK]; /* Open object lock semaphores */
#  if FF_FS_REENTRANT
static volatile byte
    SysLock; /* System lock flag to protect Files[] (0:no mutex, 1:unlocked, 2:locked) */
static volatile byte SysLockVolume; /* Volume id who is locking Files[] */
#  endif
#endif

#if FF_STR_VOLUME_ID
#  ifdef FF_VOLUME_STRS
static const char *const VolumeStr[FF_VOLUMES] = {FF_VOLUME_STRS}; /* Pre-defined volume ID */
#  endif
#endif

#if FF_LBA64
#  if FF_MIN_GPT > 0x100000000
#    error Wrong FF_MIN_GPT setting
#  endif
static const byte GUID_MS_Basic[16] = {0xA2, 0xA0, 0xD0, 0xEB, 0xE5, 0xB9, 0x33, 0x44,
                                       0x87, 0xC0, 0x68, 0xB6, 0xB7, 0x26, 0x99, 0xC7};
#endif

/*--------------------------------*/
/* LFN/Directory working buffer   */
/*--------------------------------*/

#if FF_USE_LFN == 0 /* Non-LFN configuration */
#  if FF_FS_EXFAT
#    error LFN must be enabled when enable exFAT
#  endif
#  define DEF_NAMBUF
#  define INIT_NAMBUF(fs)
#  define FREE_NAMBUF()
#  define LEAVE_MKFS(res) return res

#else /* LFN configurations */
#  if FF_MAX_LFN < 12 || FF_MAX_LFN > 255
#    error Wrong setting of FF_MAX_LFN
#  endif
#  if FF_LFN_BUF < FF_SFN_BUF || FF_SFN_BUF < 12
#    error Wrong setting of FF_LFN_BUF or FF_SFN_BUF
#  endif
#  if FF_LFN_UNICODE < 0 || FF_LFN_UNICODE > 3
#    error Wrong setting of FF_LFN_UNICODE
#  endif
static const byte LfnOfs[] = {
    1,  3,  5,  7,  9,  14, 16,
    18, 20, 22, 24, 28, 30}; /* FAT: Offset of LFN characters in the directory entry */
#  define MAXDIRB(nc)                                                                              \
    ((nc + 44U) / 15 *                                                                             \
     SZDIRE) /* exFAT: Size of directory entry block scratchpad buffer needed for the name length */

#  if FF_USE_LFN == 1 /* LFN enabled with static working buffer */
#    if FF_FS_EXFAT
static byte DirBuf[MAXDIRB(FF_MAX_LFN)]; /* Directory entry block scratchpad buffer */
#    endif
static char16_t LfnBuf[FF_MAX_LFN + 1]; /* LFN working buffer */
#    define DEF_NAMBUF
#    define INIT_NAMBUF(fs)
#    define FREE_NAMBUF()
#    define LEAVE_MKFS(res) return res

#  elif FF_USE_LFN == 2 /* LFN enabled with dynamic working buffer on the stack */
#    if FF_FS_EXFAT
#      define DEF_NAMBUF                                                                           \
        char16_t lbuf[FF_MAX_LFN + 1];                                                             \
        byte     dbuf[MAXDIRB(                                                                     \
            FF_MAX_LFN)]; /* LFN working buffer and directory entry block scratchpad buffer */
#      define INIT_NAMBUF(fs)                                                                      \
        {                                                                                          \
          (fs)->lfnbuf = lbuf;                                                                     \
          (fs)->dirbuf = dbuf;                                                                     \
        }
#      define FREE_NAMBUF()
#    else
#      define DEF_NAMBUF char16_t lbuf[FF_MAX_LFN + 1]; /* LFN working buffer */
#      define INIT_NAMBUF(fs)                                                                      \
        { (fs)->lfnbuf = lbuf; }
#      define FREE_NAMBUF()
#    endif
#    define LEAVE_MKFS(res) return res

#  elif FF_USE_LFN == 3 /* LFN enabled with dynamic working buffer on the heap */
#    if FF_FS_EXFAT
#      define DEF_NAMBUF                                                                           \
        char16_t                                                                                   \
            *lfn; /* Pointer to LFN working buffer and directory entry block scratchpad buffer */
#      define INIT_NAMBUF(fs)                                                                      \
        {                                                                                          \
          lfn = ff_memalloc((FF_MAX_LFN + 1) * 2 + MAXDIRB(FF_MAX_LFN));                           \
          if (!lfn) LEAVE_FF(fs, FR_NOT_ENOUGH_CORE);                                              \
          (fs)->lfnbuf = lfn;                                                                      \
          (fs)->dirbuf = (byte *)(lfn + FF_MAX_LFN + 1);                                           \
        }
#      define FREE_NAMBUF() ff_memfree(lfn)
#    else
#      define DEF_NAMBUF char16_t *lfn; /* Pointer to LFN working buffer */
#      define INIT_NAMBUF(fs)                                                                      \
        {                                                                                          \
          lfn = ff_memalloc((FF_MAX_LFN + 1) * 2);                                                 \
          if (!lfn) LEAVE_FF(fs, FR_NOT_ENOUGH_CORE);                                              \
          (fs)->lfnbuf = lfn;                                                                      \
        }
#      define FREE_NAMBUF() ff_memfree(lfn)
#    endif
#    define LEAVE_MKFS(res)                                                                        \
      {                                                                                            \
        if (!work) ff_memfree(buf);                                                                \
        return res;                                                                                \
      }
#    define MAX_MALLOC 0x8000 /* Must be >=FF_MAX_SS */

#  else
#    error Wrong setting of FF_USE_LFN

#  endif /* FF_USE_LFN == 1 */
#endif   /* FF_USE_LFN == 0 */

/*--------------------------------*/
/* Code conversion tables         */
/*--------------------------------*/

#if FF_CODE_PAGE == 0 /* Run-time code page configuration */
#  define CODEPAGE CodePage
static u16         CodePage; /* Current code page */
static const byte *ExCvt;    /* Ptr to SBCS up-case table Ct???[] (null:not used) */
static const byte *DbcTbl;   /* Ptr to DBCS code range table Dc???[] (null:not used) */

static const byte Ct437[] = TBL_CT437;
static const byte Ct720[] = TBL_CT720;
static const byte Ct737[] = TBL_CT737;
static const byte Ct771[] = TBL_CT771;
static const byte Ct775[] = TBL_CT775;
static const byte Ct850[] = TBL_CT850;
static const byte Ct852[] = TBL_CT852;
static const byte Ct855[] = TBL_CT855;
static const byte Ct857[] = TBL_CT857;
static const byte Ct860[] = TBL_CT860;
static const byte Ct861[] = TBL_CT861;
static const byte Ct862[] = TBL_CT862;
static const byte Ct863[] = TBL_CT863;
static const byte Ct864[] = TBL_CT864;
static const byte Ct865[] = TBL_CT865;
static const byte Ct866[] = TBL_CT866;
static const byte Ct869[] = TBL_CT869;
static const byte Dc932[] = TBL_DC932;
static const byte Dc936[] = TBL_DC936;
static const byte Dc949[] = TBL_DC949;
static const byte Dc950[] = TBL_DC950;

#elif FF_CODE_PAGE < 900 /* Static code page configuration (SBCS) */
#  define CODEPAGE FF_CODE_PAGE
static const byte ExCvt[] = MKCVTBL(TBL_CT, FF_CODE_PAGE);

#else /* Static code page configuration (DBCS) */
#  define CODEPAGE FF_CODE_PAGE
static const byte DbcTbl[] = MKCVTBL(TBL_DC, FF_CODE_PAGE);

#endif

/*--------------------------------------------------------------------------

   Module Private Functions

---------------------------------------------------------------------------*/

/*-----------------------------------------------------------------------*/
/* Load/Store multi-byte word in the FAT structure                       */
/*-----------------------------------------------------------------------*/

static u16 ld_word(const byte *ptr) /*	 Load a 2-byte little-endian word */
{
  u16 rv;

  rv = ptr[1];
  rv = rv << 8 | ptr[0];
  return rv;
}

static u32 ld_dword(const byte *ptr) /* Load a 4-byte little-endian word */
{
  u32 rv;

  rv = ptr[3];
  rv = rv << 8 | ptr[2];
  rv = rv << 8 | ptr[1];
  rv = rv << 8 | ptr[0];
  return rv;
}

#if FF_FS_EXFAT
static u64 ld_qword(const byte *ptr) /* Load an 8-byte little-endian word */
{
  u64 rv;

  rv = ptr[7];
  rv = rv << 8 | ptr[6];
  rv = rv << 8 | ptr[5];
  rv = rv << 8 | ptr[4];
  rv = rv << 8 | ptr[3];
  rv = rv << 8 | ptr[2];
  rv = rv << 8 | ptr[1];
  rv = rv << 8 | ptr[0];
  return rv;
}
#endif

#if !FF_FS_READONLY
static void st_word(byte *ptr, u16 val) /* Store a 2-byte word in little-endian */
{
  *ptr++   = (byte)val;
  val    >>= 8;
  *ptr++   = (byte)val;
}

static void st_dword(byte *ptr, u32 val) /* Store a 4-byte word in little-endian */
{
  *ptr++   = (byte)val;
  val    >>= 8;
  *ptr++   = (byte)val;
  val    >>= 8;
  *ptr++   = (byte)val;
  val    >>= 8;
  *ptr++   = (byte)val;
}

#  if FF_FS_EXFAT
static void st_qword(byte *ptr, u64 val) /* Store an 8-byte word in little-endian */
{
  *ptr++   = (byte)val;
  val    >>= 8;
  *ptr++   = (byte)val;
  val    >>= 8;
  *ptr++   = (byte)val;
  val    >>= 8;
  *ptr++   = (byte)val;
  val    >>= 8;
  *ptr++   = (byte)val;
  val    >>= 8;
  *ptr++   = (byte)val;
  val    >>= 8;
  *ptr++   = (byte)val;
  val    >>= 8;
  *ptr++   = (byte)val;
}
#  endif
#endif /* !FF_FS_READONLY */

/*-----------------------------------------------------------------------*/
/* String functions                                                      */
/*-----------------------------------------------------------------------*/

/* Test if the byte is DBC 1st byte */
static int dbc_1st(byte c) {
#if FF_CODE_PAGE == 0 /* Variable code page */
  if (DbcTbl && c >= DbcTbl[0]) {
    if (c <= DbcTbl[1]) return 1;                   /* 1st byte range 1 */
    if (c >= DbcTbl[2] && c <= DbcTbl[3]) return 1; /* 1st byte range 2 */
  }
#elif FF_CODE_PAGE >= 900 /* DBCS fixed code page */
  if (c >= DbcTbl[0]) {
    if (c <= DbcTbl[1]) return 1;
    if (c >= DbcTbl[2] && c <= DbcTbl[3]) return 1;
  }
#else                     /* SBCS fixed code page */
  if (c != 0) return 0; /* Always false */
#endif
  return 0;
}

/* Test if the byte is DBC 2nd byte */
static int dbc_2nd(byte c) {
#if FF_CODE_PAGE == 0 /* Variable code page */
  if (DbcTbl && c >= DbcTbl[4]) {
    if (c <= DbcTbl[5]) return 1;                   /* 2nd byte range 1 */
    if (c >= DbcTbl[6] && c <= DbcTbl[7]) return 1; /* 2nd byte range 2 */
    if (c >= DbcTbl[8] && c <= DbcTbl[9]) return 1; /* 2nd byte range 3 */
  }
#elif FF_CODE_PAGE >= 900 /* DBCS fixed code page */
  if (c >= DbcTbl[4]) {
    if (c <= DbcTbl[5]) return 1;
    if (c >= DbcTbl[6] && c <= DbcTbl[7]) return 1;
    if (c >= DbcTbl[8] && c <= DbcTbl[9]) return 1;
  }
#else                     /* SBCS fixed code page */
  if (c != 0) return 0; /* Always false */
#endif
  return 0;
}

#if FF_USE_LFN

/* Get a Unicode code point from the TCHAR string in defined API encodeing */
static u32
tchar2uni(/* Returns a character in UTF-16 encoding (>=0x10000 on surrogate pair, 0xFFFFFFFF on decode error) */
          const TCHAR **str /* Pointer to pointer to TCHAR string in configured encoding */
) {
  u32          uc;
  const TCHAR *p = *str;

#  if FF_LFN_UNICODE == 1 /* UTF-16 input */
  char16_t wc;

  uc = *p++;                                                       /* Get a unit */
  if (IsSurrogate(uc)) {                                           /* Surrogate? */
    wc = *p++;                                                     /* Get low surrogate */
    if (!IsSurrogateH(uc) || !IsSurrogateL(wc)) return 0xFFFFFFFF; /* Wrong surrogate? */
    uc = uc << 16 | wc;
  }

#  elif FF_LFN_UNICODE == 2 /* UTF-8 input */
  byte b;
  int  nf;

  uc = (byte)*p++;             /* Get an encoding unit */
  if (uc & 0x80) {             /* Multiple byte code? */
    if ((uc & 0xE0) == 0xC0) { /* 2-byte sequence? */
      uc &= 0x1F;
      nf  = 1;
    } else if ((uc & 0xF0) == 0xE0) { /* 3-byte sequence? */
      uc &= 0x0F;
      nf  = 2;
    } else if ((uc & 0xF8) == 0xF0) { /* 4-byte sequence? */
      uc &= 0x07;
      nf  = 3;
    } else { /* Wrong sequence */
      return 0xFFFFFFFF;
    }
    do { /* Get trailing bytes */
      b = (byte)*p++;
      if ((b & 0xC0) != 0x80) return 0xFFFFFFFF; /* Wrong sequence? */
      uc = uc << 6 | (b & 0x3F);
    } while (--nf != 0);
    if (uc < 0x80 || IsSurrogate(uc) || uc >= 0x110000) return 0xFFFFFFFF; /* Wrong code? */
    if (uc >= 0x010000)
      uc = 0xD800DC00 | ((uc - 0x10000) << 6 & 0x3FF0000) |
           (uc & 0x3FF); /* Make a surrogate pair if needed */
  }

#  elif FF_LFN_UNICODE == 3 /* UTF-32 input */
  uc = (TCHAR)*p++;                                         /* Get a unit */
  if (uc >= 0x110000 || IsSurrogate(uc)) return 0xFFFFFFFF; /* Wrong code? */
  if (uc >= 0x010000)
    uc = 0xD800DC00 | ((uc - 0x10000) << 6 & 0x3FF0000) |
         (uc & 0x3FF); /* Make a surrogate pair if needed */

#  else /* ANSI/OEM input */
  byte     b;
  char16_t wc;

  wc = (byte)*p++;                      /* Get a byte */
  if (dbc_1st((byte)wc)) {              /* Is it a DBC 1st byte? */
    b = (byte)*p++;                     /* Get 2nd byte */
    if (!dbc_2nd(b)) return 0xFFFFFFFF; /* Invalid code? */
    wc = (wc << 8) + b;                 /* Make a DBC */
  }
  if (wc != 0) {
    wc = ff_oem2uni(wc, CODEPAGE);  /* ANSI/OEM ==> Unicode */
    if (wc == 0) return 0xFFFFFFFF; /* Invalid code? */
  }
  uc = wc;

#  endif
  *str = p; /* Next read pointer */
  return uc;
}

/* Store a Unicode char in defined API encoding */
static uint
put_utf(/* Returns number of encoding units written (0:buffer overflow or wrong encoding) */
        u32    chr, /* UTF-16 encoded character (Surrogate pair if >=0x10000) */
        TCHAR *buf, /* Output buffer */
        uint   szb  /* Size of the buffer */
) {
#  if FF_LFN_UNICODE == 1 /* UTF-16 output */
  char16_t hs, wc;

  hs = (char16_t)(chr >> 16);
  wc = (char16_t)chr;
  if (hs == 0) {                              /* Single encoding unit? */
    if (szb < 1 || IsSurrogate(wc)) return 0; /* Buffer overflow or wrong code? */
    *buf = wc;
    return 1;
  }
  if (szb < 2 || !IsSurrogateH(hs) || !IsSurrogateL(wc))
    return 0; /* Buffer overflow or wrong surrogate? */
  *buf++ = hs;
  *buf++ = wc;
  return 2;

#  elif FF_LFN_UNICODE == 2 /* UTF-8 output */
  u32 hc;

  if (chr < 0x80) {        /* Single byte code? */
    if (szb < 1) return 0; /* Buffer overflow? */
    *buf = (TCHAR)chr;
    return 1;
  }
  if (chr < 0x800) {       /* 2-byte sequence? */
    if (szb < 2) return 0; /* Buffer overflow? */
    *buf++ = (TCHAR)(0xC0 | (chr >> 6 & 0x1F));
    *buf++ = (TCHAR)(0x80 | (chr >> 0 & 0x3F));
    return 2;
  }
  if (chr < 0x10000) {                         /* 3-byte sequence? */
    if (szb < 3 || IsSurrogate(chr)) return 0; /* Buffer overflow or wrong code? */
    *buf++ = (TCHAR)(0xE0 | (chr >> 12 & 0x0F));
    *buf++ = (TCHAR)(0x80 | (chr >> 6 & 0x3F));
    *buf++ = (TCHAR)(0x80 | (chr >> 0 & 0x3F));
    return 3;
  }
  /* 4-byte sequence */
  if (szb < 4) return 0;                        /* Buffer overflow? */
  hc  = ((chr & 0xFFFF0000) - 0xD8000000) >> 6; /* Get high 10 bits */
  chr = (chr & 0xFFFF) - 0xDC00;                /* Get low 10 bits */
  if (hc >= 0x100000 || chr >= 0x400) return 0; /* Wrong surrogate? */
  chr    = (hc | chr) + 0x10000;
  *buf++ = (TCHAR)(0xF0 | (chr >> 18 & 0x07));
  *buf++ = (TCHAR)(0x80 | (chr >> 12 & 0x3F));
  *buf++ = (TCHAR)(0x80 | (chr >> 6 & 0x3F));
  *buf++ = (TCHAR)(0x80 | (chr >> 0 & 0x3F));
  return 4;

#  elif FF_LFN_UNICODE == 3 /* UTF-32 output */
  u32 hc;

  if (szb < 1) return 0;                          /* Buffer overflow? */
  if (chr >= 0x10000) {                           /* Out of BMP? */
    hc  = ((chr & 0xFFFF0000) - 0xD8000000) >> 6; /* Get high 10 bits */
    chr = (chr & 0xFFFF) - 0xDC00;                /* Get low 10 bits */
    if (hc >= 0x100000 || chr >= 0x400) return 0; /* Wrong surrogate? */
    chr = (hc | chr) + 0x10000;
  }
  *buf++ = (TCHAR)chr;
  return 1;

#  else /* ANSI/OEM output */
  char16_t wc;

  wc = ff_uni2oem(chr, CODEPAGE);
  if (wc >= 0x100) { /* Is this a DBC? */
    if (szb < 2) return 0;
    *buf++ = (char)(wc >> 8); /* Store DBC 1st byte */
    *buf++ = (TCHAR)wc;       /* Store DBC 2nd byte */
    return 2;
  }
  if (wc == 0 || szb < 1) return 0; /* Invalid char or buffer overflow? */
  *buf++ = (TCHAR)wc;               /* Store the character */
  return 1;
#  endif
}
#endif /* FF_USE_LFN */

#if FF_FS_REENTRANT
/*-----------------------------------------------------------------------*/
/* Request/Release grant to access the volume                            */
/*-----------------------------------------------------------------------*/

static int lock_volume(               /* 1:Ok, 0:timeout */
                       FATFS *fs,     /* Filesystem object to lock */
                       int    syslock /* System lock required */
) {
  int rv;

#  if FF_FS_LOCK
  rv = ff_mutex_take(fs->ldrv);     /* Lock the volume */
  if (rv && syslock) {              /* System lock reqiered? */
    rv = ff_mutex_take(FF_VOLUMES); /* Lock the system */
    if (rv) {
      SysLockVolume = fs->ldrv;
      SysLock       = 2; /* System lock succeeded */
    } else {
      ff_mutex_give(fs->ldrv); /* Failed system lock */
    }
  }
#  else
  rv = syslock
           ? ff_mutex_take(fs->ldrv)
           : ff_mutex_take(fs->ldrv); /* Lock the volume (this is to prevent compiler warning) */
#  endif
  return rv;
}

static void unlock_volume(FATFS  *fs, /* Filesystem object */
                          FRESULT res /* Result code to be returned */
) {
  if (fs && res != FR_NOT_ENABLED && res != FR_INVALID_DRIVE && res != FR_TIMEOUT) {
#  if FF_FS_LOCK
    if (SysLock == 2 &&
        SysLockVolume == fs->ldrv) { /* Unlock system if it has been locked by this task */
      SysLock = 1;
      ff_mutex_give(FF_VOLUMES);
    }
#  endif
    ff_mutex_give(fs->ldrv); /* Unlock the volume */
  }
}

#endif

#if FF_FS_LOCK
/*-----------------------------------------------------------------------*/
/* File shareing control functions                                       */
/*-----------------------------------------------------------------------*/

static FRESULT
chk_share(         /* Check if the file can be accessed */
          DIR *dp, /* Directory object pointing the file to be checked */
          int acc /* Desired access type (0:Read mode open, 1:Write mode open, 2:Delete or rename) */
) {
  uint i, be;

  /* Search open object table for the object */
  be = 0;
  for (i = 0; i < FF_FS_LOCK; i++) {
    if (Files[i].fs) {                 /* Existing entry */
      if (Files[i].fs == dp->obj.fs && /* Check if the object matches with an open object */
          Files[i].clu == dp->obj.sclust && Files[i].ofs == dp->dptr)
        break;
    } else { /* Blank entry */
      be = 1;
    }
  }
  if (i == FF_FS_LOCK) { /* The object has not been opened */
    return (!be && acc != 2) ? FR_TOO_MANY_OPEN_FILES
                             : FR_OK; /* Is there a blank entry for new object? */
  }

  /* The object was opened. Reject any open against writing file and all write mode open */
  return (acc != 0 || Files[i].ctr == 0x100) ? FR_LOCKED : FR_OK;
}

static int enq_share(void) /* Check if an entry is available for a new object */
{
  uint i;

  for (i = 0; i < FF_FS_LOCK && Files[i].fs; i++)
    ; /* Find a free entry */
  return (i == FF_FS_LOCK) ? 0 : 1;
}

static uint inc_share(/* Increment object open counter and returns its index (0:Internal error) */
                      DIR *dp, /* Directory object pointing the file to register or increment */
                      int  acc /* Desired access (0:Read, 1:Write, 2:Delete/Rename) */
) {
  uint i;

  for (i = 0; i < FF_FS_LOCK; i++) { /* Find the object */
    if (Files[i].fs == dp->obj.fs && Files[i].clu == dp->obj.sclust && Files[i].ofs == dp->dptr)
      break;
  }

  if (i == FF_FS_LOCK) { /* Not opened. Register it as new. */
    for (i = 0; i < FF_FS_LOCK && Files[i].fs; i++)
      ;                            /* Find a free entry */
    if (i == FF_FS_LOCK) return 0; /* No free entry to register (int err) */
    Files[i].fs  = dp->obj.fs;
    Files[i].clu = dp->obj.sclust;
    Files[i].ofs = dp->dptr;
    Files[i].ctr = 0;
  }

  if (acc >= 1 && Files[i].ctr) return 0; /* Access violation (int err) */

  Files[i].ctr = acc ? 0x100 : Files[i].ctr + 1; /* Set semaphore value */

  return i + 1; /* Index number origin from 1 */
}

static FRESULT dec_share(       /* Decrement object open counter */
                         uint i /* Semaphore index (1..) */
) {
  uint    n;
  FRESULT res;

  if (--i < FF_FS_LOCK) { /* Index number origin from 0 */
    n = Files[i].ctr;
    if (n == 0x100) n = 0; /* If write mode open, delete the object semaphore */
    if (n > 0) n--;        /* Decrement read mode open count */
    Files[i].ctr = n;
    if (n == 0) { /* Delete the object semaphore if open count becomes zero */
      Files[i].fs =
          0; /* Free the entry <<<If this memory write operation is not in atomic, FF_FS_REENTRANT == 1 and FF_VOLUMES > 1, there is a potential error in this process >>> */
    }
    res = FR_OK;
  } else {
    res = FR_INT_ERR; /* Invalid index number */
  }
  return res;
}

static void clear_share(/* Clear all lock entries of the volume */
                        FATFS *fs) {
  uint i;

  for (i = 0; i < FF_FS_LOCK; i++) {
    if (Files[i].fs == fs) Files[i].fs = 0;
  }
}

#endif /* FF_FS_LOCK */

/*-----------------------------------------------------------------------*/
/* Move/Flush disk access window in the filesystem object                */
/*-----------------------------------------------------------------------*/
#if !FF_FS_READONLY
static FRESULT sync_window(          /* Returns FR_OK or FR_DISK_ERR */
                           FATFS *fs /* Filesystem object */
) {
  FRESULT res = FR_OK;

  if (fs->wflag) { /* Is the disk access window dirty? */
    if (disk_write(fs->pdrv, fs->win, fs->winsect, 1) ==
        RES_OK) {                                  /* Write it back into the volume */
      fs->wflag = 0;                               /* Clear window dirty flag */
      if (fs->winsect - fs->fatbase < fs->fsize) { /* Is it in the 1st FAT? */
        if (fs->n_fats == 2)
          disk_write(fs->pdrv, fs->win, fs->winsect + fs->fsize,
                     1); /* Reflect it to 2nd FAT if needed */
      }
    } else {
      res = FR_DISK_ERR;
    }
  }
  return res;
}
#endif

static FRESULT move_window(            /* Returns FR_OK or FR_DISK_ERR */
                           FATFS *fs,  /* Filesystem object */
                           LBA_t  sect /* Sector LBA to make appearance in the fs->win[] */
) {
  FRESULT res = FR_OK;

  if (sect != fs->winsect) { /* Window offset changed? */
#if !FF_FS_READONLY
    res = sync_window(fs); /* Flush the window */
#endif
    if (res == FR_OK) { /* Fill sector window with new data */
      if (disk_read(fs->pdrv, fs->win, sect, 1) != RES_OK) {
        sect = (LBA_t)0 - 1; /* Invalidate window if read data is not valid */
        res  = FR_DISK_ERR;
      }
      fs->winsect = sect;
    }
  }
  return res;
}

#if !FF_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Synchronize filesystem and data on the storage                        */
/*-----------------------------------------------------------------------*/

static FRESULT sync_fs(          /* Returns FR_OK or FR_DISK_ERR */
                       FATFS *fs /* Filesystem object */
) {
  FRESULT res;

  res = sync_window(fs);
  if (res == FR_OK) {
    if (fs->fs_type == FS_FAT32 && fs->fsi_flag == 1) { /* FAT32: Update FSInfo sector if needed */
      /* Create FSInfo structure */
      memset(fs->win, 0, sizeof fs->win);
      st_word(fs->win + BS_55AA, 0xAA55);                /* Boot signature */
      st_dword(fs->win + FSI_LeadSig, 0x41615252);       /* Leading signature */
      st_dword(fs->win + FSI_StrucSig, 0x61417272);      /* Structure signature */
      st_dword(fs->win + FSI_Free_Count, fs->free_clst); /* Number of free clusters */
      st_dword(fs->win + FSI_Nxt_Free, fs->last_clst);   /* Last allocated culuster */
      fs->winsect = fs->volbase + 1; /* Write it into the FSInfo sector (Next to VBR) */
      disk_write(fs->pdrv, fs->win, fs->winsect, 1);
      fs->fsi_flag = 0;
    }
    /* Make sure that no pending write process in the lower layer */
    if (disk_ioctl(fs->pdrv, CTRL_SYNC, 0) != RES_OK) res = FR_DISK_ERR;
  }

  return res;
}

#endif

/*-----------------------------------------------------------------------*/
/* Get physical sector number from cluster number                        */
/*-----------------------------------------------------------------------*/

static LBA_t clst2sect(            /* !=0:Sector number, 0:Failed (invalid cluster#) */
                       FATFS *fs,  /* Filesystem object */
                       u32    clst /* Cluster# to be converted */
) {
  clst -= 2;                                     /* Cluster number is origin from 2 */
  if (clst >= fs->n_fatent - 2) return 0;        /* Is it invalid cluster number? */
  return fs->database + (LBA_t)fs->csize * clst; /* Start sector number of the cluster */
}

/*-----------------------------------------------------------------------*/
/* FAT access - Read value of an FAT entry                               */
/*-----------------------------------------------------------------------*/

static u32 get_fat(/* 0xFFFFFFFF:Disk error, 1:Internal error, 2..0x7FFFFFFF:Cluster status */
                   FFOBJID *obj, /* Corresponding object */
                   u32      clst /* Cluster number to get the value */
) {
  uint   wc, bc;
  u32    val;
  FATFS *fs = obj->fs;

  if (clst < 2 || clst >= fs->n_fatent) { /* Check if in valid range */
    val = 1;                              /* Internal error */

  } else {
    val = 0xFFFFFFFF; /* Default value falls on disk error */

    switch (fs->fs_type) {
    case FS_FAT12:
      bc  = (uint)clst;
      bc += bc / 2;
      if (move_window(fs, fs->fatbase + (bc / SS(fs))) != FR_OK) break;
      wc = fs->win[bc++ % SS(fs)]; /* Get 1st byte of the entry */
      if (move_window(fs, fs->fatbase + (bc / SS(fs))) != FR_OK) break;
      wc  |= fs->win[bc % SS(fs)] << 8;             /* Merge 2nd byte of the entry */
      val  = (clst & 1) ? (wc >> 4) : (wc & 0xFFF); /* Adjust bit position */
      break;

    case FS_FAT16:
      if (move_window(fs, fs->fatbase + (clst / (SS(fs) / 2))) != FR_OK) break;
      val = ld_word(fs->win + clst * 2 % SS(fs)); /* Simple u16 array */
      break;

    case FS_FAT32:
      if (move_window(fs, fs->fatbase + (clst / (SS(fs) / 4))) != FR_OK) break;
      val = ld_dword(fs->win + clst * 4 % SS(fs)) &
            0x0FFFFFFF; /* Simple u32 array but mask out upper 4 bits */
      break;
#if FF_FS_EXFAT
    case FS_EXFAT:
      if ((obj->objsize != 0 && obj->sclust != 0) ||
          obj->stat == 0) {            /* Object except root dir must have valid data length */
        u32 cofs = clst - obj->sclust; /* Offset from start cluster */
        u32 clen =
            (u32)((LBA_t)((obj->objsize - 1) / SS(fs)) / fs->csize); /* Number of clusters - 1 */

        if (obj->stat == 2 && cofs <= clen) {           /* Is it a contiguous chain? */
          val = (cofs == clen) ? 0x7FFFFFFF : clst + 1; /* No data on the FAT, generate the value */
          break;
        }
        if (obj->stat == 3 && cofs < obj->n_cont) { /* Is it in the 1st fragment? */
          val = clst + 1;                           /* Generate the value */
          break;
        }
        if (obj->stat != 2) {     /* Get value from FAT if FAT chain is valid */
          if (obj->n_frag != 0) { /* Is it on the growing edge? */
            val = 0x7FFFFFFF;     /* Generate EOC */
          } else {
            if (move_window(fs, fs->fatbase + (clst / (SS(fs) / 4))) != FR_OK) break;
            val = ld_dword(fs->win + clst * 4 % SS(fs)) & 0x7FFFFFFF;
          }
          break;
        }
      }
      val = 1; /* Internal error */
      break;
#endif
    default: val = 1; /* Internal error */
    }
  }

  return val;
}

#if !FF_FS_READONLY
/*-----------------------------------------------------------------------*/
/* FAT access - Change value of an FAT entry                             */
/*-----------------------------------------------------------------------*/

static FRESULT put_fat(             /* FR_OK(0):succeeded, !=0:error */
                       FATFS *fs,   /* Corresponding filesystem object */
                       u32    clst, /* FAT index number (cluster number) to be changed */
                       u32    val   /* New value to be set to the entry */
) {
  uint    bc;
  byte   *p;
  FRESULT res = FR_INT_ERR;

  if (clst >= 2 && clst < fs->n_fatent) { /* Check if in valid range */
    switch (fs->fs_type) {
    case FS_FAT12:
      bc   = (uint)clst;
      bc  += bc / 2; /* bc: byte offset of the entry */
      res  = move_window(fs, fs->fatbase + (bc / SS(fs)));
      if (res != FR_OK) break;
      p         = fs->win + bc++ % SS(fs);
      *p        = (clst & 1) ? ((*p & 0x0F) | ((byte)val << 4)) : (byte)val; /* Update 1st byte */
      fs->wflag = 1;
      res       = move_window(fs, fs->fatbase + (bc / SS(fs)));
      if (res != FR_OK) break;
      p         = fs->win + bc % SS(fs);
      *p        = (clst & 1) ? (byte)(val >> 4)
                             : ((*p & 0xF0) | ((byte)(val >> 8) & 0x0F)); /* Update 2nd byte */
      fs->wflag = 1;
      break;

    case FS_FAT16:
      res = move_window(fs, fs->fatbase + (clst / (SS(fs) / 2)));
      if (res != FR_OK) break;
      st_word(fs->win + clst * 2 % SS(fs), (u16)val); /* Simple u16 array */
      fs->wflag = 1;
      break;

    case FS_FAT32:
#  if FF_FS_EXFAT
    case FS_EXFAT:
#  endif
      res = move_window(fs, fs->fatbase + (clst / (SS(fs) / 4)));
      if (res != FR_OK) break;
      if (!FF_FS_EXFAT || fs->fs_type != FS_EXFAT) {
        val = (val & 0x0FFFFFFF) | (ld_dword(fs->win + clst * 4 % SS(fs)) & 0xF0000000);
      }
      st_dword(fs->win + clst * 4 % SS(fs), val);
      fs->wflag = 1;
      break;
    }
  }
  return res;
}

#endif /* !FF_FS_READONLY */

#if FF_FS_EXFAT && !FF_FS_READONLY
/*-----------------------------------------------------------------------*/
/* exFAT: Accessing FAT and Allocation Bitmap                            */
/*-----------------------------------------------------------------------*/

/*--------------------------------------*/
/* Find a contiguous free cluster block */
/*--------------------------------------*/

static u32 find_bitmap(           /* 0:Not found, 2..:Cluster block found, 0xFFFFFFFF:Disk error */
                       FATFS *fs, /* Filesystem object */
                       u32    clst, /* Cluster number to scan from */
                       u32    ncl   /* Number of contiguous clusters to find (1..) */
) {
  byte bm, bv;
  uint i;
  u32  val, scl, ctr;

  clst -= 2; /* The first bit in the bitmap corresponds to cluster #2 */
  if (clst >= fs->n_fatent - 2) clst = 0;
  scl = val = clst;
  ctr       = 0;
  for (;;) {
    if (move_window(fs, fs->bitbase + val / 8 / SS(fs)) != FR_OK) return 0xFFFFFFFF;
    i  = val / 8 % SS(fs);
    bm = 1 << (val % 8);
    do {
      do {
        bv   = fs->win[i] & bm;
        bm <<= 1;                        /* Get bit value */
        if (++val >= fs->n_fatent - 2) { /* Next cluster (with wrap-around) */
          val = 0;
          bm  = 0;
          i   = SS(fs);
        }
        if (bv == 0) {                      /* Is it a free cluster? */
          if (++ctr == ncl) return scl + 2; /* Check if run length is sufficient for required */
        } else {
          scl = val;
          ctr = 0; /* Encountered a cluster in-use, restart to scan */
        }
        if (val == clst) return 0; /* All cluster scanned? */
      } while (bm != 0);
      bm = 1;
    } while (++i < SS(fs));
  }
}

/*----------------------------------------*/
/* Set/Clear a block of allocation bitmap */
/*----------------------------------------*/

static FRESULT change_bitmap(FATFS *fs,   /* Filesystem object */
                             u32    clst, /* Cluster number to change from */
                             u32    ncl,  /* Number of clusters to be changed */
                             int    bv    /* bit value to be set (0 or 1) */
) {
  byte  bm;
  uint  i;
  LBA_t sect;

  clst -= 2;                               /* The first bit corresponds to cluster #2 */
  sect  = fs->bitbase + clst / 8 / SS(fs); /* Sector address */
  i     = clst / 8 % SS(fs);               /* Byte offset in the sector */
  bm    = 1 << (clst % 8);                 /* Bit mask in the byte */
  for (;;) {
    if (move_window(fs, sect++) != FR_OK) return FR_DISK_ERR;
    do {
      do {
        if (bv == (int)((fs->win[i] & bm) != 0)) return FR_INT_ERR; /* Is the bit expected value? */
        fs->win[i] ^= bm;                                           /* Flip the bit */
        fs->wflag   = 1;
        if (--ncl == 0) return FR_OK; /* All bits processed? */
      } while (bm <<= 1);             /* Next bit */
      bm = 1;
    } while (++i < SS(fs)); /* Next byte */
    i = 0;
  }
}

/*---------------------------------------------*/
/* Fill the first fragment of the FAT chain    */
/*---------------------------------------------*/

static FRESULT fill_first_frag(FFOBJID *obj /* Pointer to the corresponding object */
) {
  FRESULT res;
  u32     cl, n;

  if (obj->stat == 3) { /* Has the object been changed 'fragmented' in this session? */
    for (cl = obj->sclust, n = obj->n_cont; n; cl++, n--) { /* Create cluster chain on the FAT */
      res = put_fat(obj->fs, cl, cl + 1);
      if (res != FR_OK) return res;
    }
    obj->stat = 0; /* Change status 'FAT chain is valid' */
  }
  return FR_OK;
}

/*---------------------------------------------*/
/* Fill the last fragment of the FAT chain     */
/*---------------------------------------------*/

static FRESULT fill_last_frag(FFOBJID *obj, /* Pointer to the corresponding object */
                              u32      lcl, /* Last cluster of the fragment */
                              u32      term /* Value to set the last FAT entry */
) {
  FRESULT res;

  while (obj->n_frag > 0) { /* Create the chain of last fragment */
    res = put_fat(obj->fs, lcl - obj->n_frag + 1, (obj->n_frag > 1) ? lcl - obj->n_frag + 2 : term);
    if (res != FR_OK) return res;
    obj->n_frag--;
  }
  return FR_OK;
}

#endif /* FF_FS_EXFAT && !FF_FS_READONLY */

#if !FF_FS_READONLY
/*-----------------------------------------------------------------------*/
/* FAT handling - Remove a cluster chain                                 */
/*-----------------------------------------------------------------------*/

static FRESULT remove_chain(               /* FR_OK(0):succeeded, !=0:error */
                            FFOBJID *obj,  /* Corresponding object */
                            u32      clst, /* Cluster to remove a chain from */
                            u32      pclst /* Previous cluster of clst (0 if entire chain) */
) {
  FRESULT res = FR_OK;
  u32     nxt;
  FATFS  *fs = obj->fs;
#  if FF_FS_EXFAT || FF_USE_TRIM
  u32 scl = clst, ecl = clst;
#  endif
#  if FF_USE_TRIM
  LBA_t rt[2];
#  endif

  if (clst < 2 || clst >= fs->n_fatent) return FR_INT_ERR; /* Check if in valid range */

  /* Mark the previous cluster 'EOC' on the FAT if it exists */
  if (pclst != 0 && (!FF_FS_EXFAT || fs->fs_type != FS_EXFAT || obj->stat != 2)) {
    res = put_fat(fs, pclst, 0xFFFFFFFF);
    if (res != FR_OK) return res;
  }

  /* Remove the chain */
  do {
    nxt = get_fat(obj, clst);                  /* Get cluster status */
    if (nxt == 0) break;                       /* Empty cluster? */
    if (nxt == 1) return FR_INT_ERR;           /* Internal error? */
    if (nxt == 0xFFFFFFFF) return FR_DISK_ERR; /* Disk error? */
    if (!FF_FS_EXFAT || fs->fs_type != FS_EXFAT) {
      res = put_fat(fs, clst, 0); /* Mark the cluster 'free' on the FAT */
      if (res != FR_OK) return res;
    }
    if (fs->free_clst < fs->n_fatent - 2) { /* Update FSINFO */
      fs->free_clst++;
      fs->fsi_flag |= 1;
    }
#  if FF_FS_EXFAT || FF_USE_TRIM
    if (ecl + 1 == nxt) { /* Is next cluster contiguous? */
      ecl = nxt;
    } else { /* End of contiguous cluster block */
#    if FF_FS_EXFAT
      if (fs->fs_type == FS_EXFAT) {
        res = change_bitmap(fs, scl, ecl - scl + 1,
                            0); /* Mark the cluster block 'free' on the bitmap */
        if (res != FR_OK) return res;
      }
#    endif
#    if FF_USE_TRIM
      rt[0] = clst2sect(fs, scl);                 /* Start of data area to be freed */
      rt[1] = clst2sect(fs, ecl) + fs->csize - 1; /* End of data area to be freed */
      disk_ioctl(fs->pdrv, CTRL_TRIM,
                 rt); /* Inform storage device that the data in the block may be erased */
#    endif
      scl = ecl = nxt;
    }
#  endif
    clst = nxt;                  /* Next cluster */
  } while (clst < fs->n_fatent); /* Repeat while not the last link */

#  if FF_FS_EXFAT
  /* Some post processes for chain status */
  if (fs->fs_type == FS_EXFAT) {
    if (pclst == 0) { /* Has the entire chain been removed? */
      obj->stat = 0;  /* Change the chain status 'initial' */
    } else {
      if (obj->stat == 0) { /* Is it a fragmented chain from the beginning of this session? */
        clst = obj->sclust; /* Follow the chain to check if it gets contiguous */
        while (clst != pclst) {
          nxt = get_fat(obj, clst);
          if (nxt < 2) return FR_INT_ERR;
          if (nxt == 0xFFFFFFFF) return FR_DISK_ERR;
          if (nxt != clst + 1) break; /* Not contiguous? */
          clst++;
        }
        if (clst == pclst) { /* Has the chain got contiguous again? */
          obj->stat = 2;     /* Change the chain status 'contiguous' */
        }
      } else {
        if (obj->stat == 3 && pclst >= obj->sclust &&
            pclst <=
                obj->sclust +
                    obj->n_cont) { /* Was the chain fragmented in this session and got contiguous again? */
          obj->stat = 2;           /* Change the chain status 'contiguous' */
        }
      }
    }
  }
#  endif
  return FR_OK;
}

/*-----------------------------------------------------------------------*/
/* FAT handling - Stretch a chain or Create a new chain                  */
/*-----------------------------------------------------------------------*/

static u32
create_chain(/* 0:No free cluster, 1:Internal error, 0xFFFFFFFF:Disk error, >=2:New cluster# */
             FFOBJID *obj, /* Corresponding object */
             u32      clst /* Cluster# to stretch, 0:Create a new chain */
) {
  u32     cs, ncl, scl;
  FRESULT res;
  FATFS  *fs = obj->fs;

  if (clst == 0) {       /* Create a new chain */
    scl = fs->last_clst; /* Suggested cluster to start to find */
    if (scl == 0 || scl >= fs->n_fatent) scl = 1;
  } else {                            /* Stretch a chain */
    cs = get_fat(obj, clst);          /* Check the cluster status */
    if (cs < 2) return 1;             /* Test for insanity */
    if (cs == 0xFFFFFFFF) return cs;  /* Test for disk error */
    if (cs < fs->n_fatent) return cs; /* It is already followed by next cluster */
    scl = clst;                       /* Cluster to start to find */
  }
  if (fs->free_clst == 0) return 0; /* No free cluster */

#  if FF_FS_EXFAT
  if (fs->fs_type == FS_EXFAT) {                   /* On the exFAT volume */
    ncl = find_bitmap(fs, scl, 1);                 /* Find a free cluster */
    if (ncl == 0 || ncl == 0xFFFFFFFF) return ncl; /* No free cluster or hard error? */
    res = change_bitmap(fs, ncl, 1, 1);            /* Mark the cluster 'in use' */
    if (res == FR_INT_ERR) return 1;
    if (res == FR_DISK_ERR) return 0xFFFFFFFF;
    if (clst == 0) {                          /* Is it a new chain? */
      obj->stat = 2;                          /* Set status 'contiguous' */
    } else {                                  /* It is a stretched chain */
      if (obj->stat == 2 && ncl != scl + 1) { /* Is the chain got fragmented? */
        obj->n_cont = scl - obj->sclust;      /* Set size of the contiguous part */
        obj->stat   = 3;                      /* Change status 'just fragmented' */
      }
    }
    if (obj->stat != 2) {                                /* Is the file non-contiguous? */
      if (ncl == clst + 1) {                             /* Is the cluster next to previous one? */
        obj->n_frag = obj->n_frag ? obj->n_frag + 1 : 2; /* Increment size of last framgent */
      } else {                                           /* New fragment */
        if (obj->n_frag == 0) obj->n_frag = 1;
        res = fill_last_frag(obj, clst,
                             ncl); /* Fill last fragment on the FAT and link it to new one */
        if (res == FR_OK) obj->n_frag = 1;
      }
    }
  } else
#  endif
  { /* On the FAT/FAT32 volume */
    ncl = 0;
    if (scl == clst) { /* Stretching an existing chain? */
      ncl = scl + 1;   /* Test if next cluster is free */
      if (ncl >= fs->n_fatent) ncl = 2;
      cs = get_fat(obj, ncl);                     /* Get next cluster status */
      if (cs == 1 || cs == 0xFFFFFFFF) return cs; /* Test for error */
      if (cs != 0) {                              /* Not free? */
        cs = fs->last_clst;                       /* Start at suggested cluster if it is valid */
        if (cs >= 2 && cs < fs->n_fatent) scl = cs;
        ncl = 0;
      }
    }
    if (ncl == 0) { /* The new cluster cannot be contiguous and find another fragment */
      ncl = scl;    /* Start cluster */
      for (;;) {
        ncl++;                     /* Next cluster */
        if (ncl >= fs->n_fatent) { /* Check wrap-around */
          ncl = 2;
          if (ncl > scl) return 0; /* No free cluster found? */
        }
        cs = get_fat(obj, ncl);                     /* Get the cluster status */
        if (cs == 0) break;                         /* Found a free cluster? */
        if (cs == 1 || cs == 0xFFFFFFFF) return cs; /* Test for error */
        if (ncl == scl) return 0;                   /* No free cluster found? */
      }
    }
    res = put_fat(fs, ncl, 0xFFFFFFFF); /* Mark the new cluster 'EOC' */
    if (res == FR_OK && clst != 0) {
      res = put_fat(fs, clst, ncl); /* Link it from the previous one if needed */
    }
  }

  if (res == FR_OK) { /* Update FSINFO if function succeeded. */
    fs->last_clst = ncl;
    if (fs->free_clst <= fs->n_fatent - 2) fs->free_clst--;
    fs->fsi_flag |= 1;
  } else {
    ncl = (res == FR_DISK_ERR) ? 0xFFFFFFFF : 1; /* Failed. Generate error status */
  }

  return ncl; /* Return new cluster number or error status */
}

#endif /* !FF_FS_READONLY */

#if FF_USE_FASTSEEK
/*-----------------------------------------------------------------------*/
/* FAT handling - Convert offset into cluster with link map table        */
/*-----------------------------------------------------------------------*/

static u32 clmt_clust(            /* <2:Error, >=2:Cluster number */
                      FIL    *fp, /* Pointer to the file object */
                      FSIZE_t ofs /* File offset to be converted to cluster# */
) {
  u32    cl, ncl;
  u32   *tbl;
  FATFS *fs = fp->obj.fs;

  tbl = fp->cltbl + 1;                   /* Top of CLMT */
  cl  = (u32)(ofs / SS(fs) / fs->csize); /* Cluster order from top of the file */
  for (;;) {
    ncl = *tbl++;           /* Number of cluters in the fragment */
    if (ncl == 0) return 0; /* End of table? (error) */
    if (cl < ncl) break;    /* In this fragment? */
    cl -= ncl;
    tbl++; /* Next fragment */
  }
  return cl + *tbl; /* Return the cluster number */
}

#endif /* FF_USE_FASTSEEK */

/*-----------------------------------------------------------------------*/
/* Directory handling - Fill a cluster with zeros                        */
/*-----------------------------------------------------------------------*/

#if !FF_FS_READONLY
static FRESULT dir_clear(            /* Returns FR_OK or FR_DISK_ERR */
                         FATFS *fs,  /* Filesystem object */
                         u32    clst /* Directory table to clear */
) {
  LBA_t sect;
  uint  n, szb;
  byte *ibuf;

  if (sync_window(fs) != FR_OK) return FR_DISK_ERR; /* Flush disk access window */
  sect        = clst2sect(fs, clst);                /* Top of the cluster */
  fs->winsect = sect;                               /* Set window to top of the cluster */
  memset(fs->win, 0, sizeof fs->win);               /* Clear window buffer */
#  if FF_USE_LFN == 3 /* Quick table clear by using multi-secter write */
  /* Allocate a temporary buffer */
  for (szb = ((u32)fs->csize * SS(fs) >= MAX_MALLOC) ? MAX_MALLOC : fs->csize * SS(fs), ibuf = 0;
       szb > SS(fs) && (ibuf = ff_memalloc(szb)) == 0; szb /= 2)
    ;
  if (szb > SS(fs)) { /* Buffer allocated? */
    memset(ibuf, 0, szb);
    szb /= SS(fs); /* Bytes -> Sectors */
    for (n = 0; n < fs->csize && disk_write(fs->pdrv, ibuf, sect + n, szb) == RES_OK; n += szb)
      ; /* Fill the cluster with 0 */
    ff_memfree(ibuf);
  } else
#  endif
  {
    ibuf = fs->win;
    szb  = 1; /* Use window buffer (many single-sector writes may take a time) */
    for (n = 0; n < fs->csize && disk_write(fs->pdrv, ibuf, sect + n, szb) == RES_OK; n += szb)
      ; /* Fill the cluster with 0 */
  }
  return (n == fs->csize) ? FR_OK : FR_DISK_ERR;
}
#endif /* !FF_FS_READONLY */

/*-----------------------------------------------------------------------*/
/* Directory handling - Set directory index                              */
/*-----------------------------------------------------------------------*/

static FRESULT dir_sdi(         /* FR_OK(0):succeeded, !=0:error */
                       DIR *dp, /* Pointer to directory object */
                       u32  ofs /* Offset of directory table */
) {
  u32    csz, clst;
  FATFS *fs = dp->obj.fs;

  if (ofs >= (u32)((FF_FS_EXFAT && fs->fs_type == FS_EXFAT) ? MAX_DIR_EX : MAX_DIR) ||
      ofs % SZDIRE) { /* Check range of offset and alignment */
    return FR_INT_ERR;
  }
  dp->dptr = ofs;                             /* Set current offset */
  clst     = dp->obj.sclust;                  /* Table start cluster (0:root) */
  if (clst == 0 && fs->fs_type >= FS_FAT32) { /* Replace cluster# 0 with root cluster# */
    clst = (u32)fs->dirbase;
    if (FF_FS_EXFAT) dp->obj.stat = 0; /* exFAT: Root dir has an FAT chain */
  }

  if (clst == 0) { /* Static table (root-directory on the FAT volume) */
    if (ofs / SZDIRE >= fs->n_rootdir) return FR_INT_ERR; /* Is index out of range? */
    dp->sect = fs->dirbase;

  } else { /* Dynamic table (sub-directory or root-directory on the FAT32/exFAT volume) */
    csz = (u32)fs->csize * SS(fs);                /* Bytes per cluster */
    while (ofs >= csz) {                          /* Follow cluster chain */
      clst = get_fat(&dp->obj, clst);             /* Get next cluster */
      if (clst == 0xFFFFFFFF) return FR_DISK_ERR; /* Disk error */
      if (clst < 2 || clst >= fs->n_fatent)
        return FR_INT_ERR; /* Reached to end of table or internal error */
      ofs -= csz;
    }
    dp->sect = clst2sect(fs, clst);
  }
  dp->clust = clst; /* Current cluster# */
  if (dp->sect == 0) return FR_INT_ERR;
  dp->sect += ofs / SS(fs);             /* Sector# of the directory entry */
  dp->dir   = fs->win + (ofs % SS(fs)); /* Pointer to the entry in the win[] */

  return FR_OK;
}

/*-----------------------------------------------------------------------*/
/* Directory handling - Move directory table index next                  */
/*-----------------------------------------------------------------------*/

static FRESULT
dir_next(             /* FR_OK(0):succeeded, FR_NO_FILE:End of table, FR_DENIED:Could not stretch */
         DIR *dp,     /* Pointer to the directory object */
         int  stretch /* 0: Do not stretch table, 1: Stretch table if needed */
) {
  u32    ofs, clst;
  FATFS *fs = dp->obj.fs;

  ofs = dp->dptr + SZDIRE; /* Next entry */
  if (ofs >= (u32)((FF_FS_EXFAT && fs->fs_type == FS_EXFAT) ? MAX_DIR_EX : MAX_DIR))
    dp->sect = 0;                       /* Disable it if the offset reached the max value */
  if (dp->sect == 0) return FR_NO_FILE; /* Report EOT if it has been disabled */

  if (ofs % SS(fs) == 0) { /* Sector changed? */
    dp->sect++;            /* Next sector */

    if (dp->clust == 0) {                  /* Static table */
      if (ofs / SZDIRE >= fs->n_rootdir) { /* Report EOT if it reached end of static table */
        dp->sect = 0;
        return FR_NO_FILE;
      }
    } else {                                        /* Dynamic table */
      if ((ofs / SS(fs) & (fs->csize - 1)) == 0) {  /* Cluster changed? */
        clst = get_fat(&dp->obj, dp->clust);        /* Get next cluster */
        if (clst <= 1) return FR_INT_ERR;           /* Internal error */
        if (clst == 0xFFFFFFFF) return FR_DISK_ERR; /* Disk error */
        if (clst >= fs->n_fatent) {                 /* It reached end of dynamic table */
#if !FF_FS_READONLY
          if (!stretch) { /* If no stretch, report EOT */
            dp->sect = 0;
            return FR_NO_FILE;
          }
          clst = create_chain(&dp->obj, dp->clust);             /* Allocate a cluster */
          if (clst == 0) return FR_DENIED;                      /* No free cluster */
          if (clst == 1) return FR_INT_ERR;                     /* Internal error */
          if (clst == 0xFFFFFFFF) return FR_DISK_ERR;           /* Disk error */
          if (dir_clear(fs, clst) != FR_OK) return FR_DISK_ERR; /* Clean up the stretched table */
          if (FF_FS_EXFAT) dp->obj.stat |= 4; /* exFAT: The directory has been stretched */
#else
          if (!stretch) dp->sect = 0; /* (this line is to suppress compiler warning) */
          dp->sect = 0;
          return FR_NO_FILE; /* Report EOT */
#endif
        }
        dp->clust = clst; /* Initialize data for new cluster */
        dp->sect  = clst2sect(fs, clst);
      }
    }
  }
  dp->dptr = ofs;                    /* Current entry */
  dp->dir  = fs->win + ofs % SS(fs); /* Pointer to the entry in the win[] */

  return FR_OK;
}

#if !FF_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Directory handling - Reserve a block of directory entries             */
/*-----------------------------------------------------------------------*/

static FRESULT dir_alloc(           /* FR_OK(0):succeeded, !=0:error */
                         DIR *dp,   /* Pointer to the directory object */
                         uint n_ent /* Number of contiguous entries to allocate */
) {
  FRESULT res;
  uint    n;
  FATFS  *fs = dp->obj.fs;

  res = dir_sdi(dp, 0);
  if (res == FR_OK) {
    n = 0;
    do {
      res = move_window(fs, dp->sect);
      if (res != FR_OK) break;
#  if FF_FS_EXFAT
      if ((fs->fs_type == FS_EXFAT) ? (int)((dp->dir[XDIR_Type] & 0x80) == 0)
                                    : (int)(dp->dir[DIR_Name] == DDEM ||
                                            dp->dir[DIR_Name] == 0)) { /* Is the entry free? */
#  else
      if (dp->dir[DIR_Name] == DDEM || dp->dir[DIR_Name] == 0) { /* Is the entry free? */
#  endif
        if (++n == n_ent) break; /* Is a block of contiguous free entries found? */
      } else {
        n = 0; /* Not a free entry, restart to search */
      }
      res = dir_next(dp, 1); /* Next entry with table stretch enabled */
    } while (res == FR_OK);
  }

  if (res == FR_NO_FILE) res = FR_DENIED; /* No directory entry to allocate */
  return res;
}

#endif /* !FF_FS_READONLY */

/*-----------------------------------------------------------------------*/
/* FAT: Directory handling - Load/Store start cluster number             */
/*-----------------------------------------------------------------------*/

static u32 ld_clust(                /* Returns the top cluster value of the SFN entry */
                    FATFS      *fs, /* Pointer to the fs object */
                    const byte *dir /* Pointer to the key entry */
) {
  u32 cl;

  cl = ld_word(dir + DIR_FstClusLO);
  if (fs->fs_type == FS_FAT32) { cl |= (u32)ld_word(dir + DIR_FstClusHI) << 16; }

  return cl;
}

#if !FF_FS_READONLY
static void st_clust(FATFS *fs,  /* Pointer to the fs object */
                     byte  *dir, /* Pointer to the key entry */
                     u32    cl   /* Value to be set */
) {
  st_word(dir + DIR_FstClusLO, (u16)cl);
  if (fs->fs_type == FS_FAT32) { st_word(dir + DIR_FstClusHI, (u16)(cl >> 16)); }
}
#endif

#if FF_USE_LFN
/*--------------------------------------------------------*/
/* FAT-LFN: Compare a part of file name with an LFN entry */
/*--------------------------------------------------------*/

static int cmp_lfn(                        /* 1:matched, 0:not matched */
                   const char16_t *lfnbuf, /* Pointer to the LFN working buffer to be compared */
                   byte *dir /* Pointer to the directory entry containing the part of LFN */
) {
  uint     i, s;
  char16_t wc, uc;

  if (ld_word(dir + LDIR_FstClusLO) != 0) return 0; /* Check LDIR_FstClusLO */

  i = ((dir[LDIR_Ord] & 0x3F) - 1) * 13; /* Offset in the LFN buffer */

  for (wc = 1, s = 0; s < 13; s++) { /* Process all characters in the entry */
    uc = ld_word(dir + LfnOfs[s]);   /* Pick an LFN character */
    if (wc != 0) {
      if (i >= FF_MAX_LFN + 1 || ff_wtoupper(uc) != ff_wtoupper(lfnbuf[i++])) { /* Compare it */
        return 0;                                                               /* Not matched */
      }
      wc = uc;
    } else {
      if (uc != 0xFFFF) return 0; /* Check filler */
    }
  }

  if ((dir[LDIR_Ord] & LLEF) && wc && lfnbuf[i])
    return 0; /* Last segment matched but different length */

  return 1; /* The part of LFN matched */
}

#  if FF_FS_MINIMIZE <= 1 || FF_FS_RPATH >= 2 || FF_USE_LABEL || FF_FS_EXFAT
/*-----------------------------------------------------*/
/* FAT-LFN: Pick a part of file name from an LFN entry */
/*-----------------------------------------------------*/

static int pick_lfn(                  /* 1:succeeded, 0:buffer overflow or invalid LFN entry */
                    char16_t *lfnbuf, /* Pointer to the LFN working buffer */
                    byte     *dir     /* Pointer to the LFN entry */
) {
  uint     i, s;
  char16_t wc, uc;

  if (ld_word(dir + LDIR_FstClusLO) != 0) return 0; /* Check LDIR_FstClusLO is 0 */

  i = ((dir[LDIR_Ord] & ~LLEF) - 1) * 13; /* Offset in the LFN buffer */

  for (wc = 1, s = 0; s < 13; s++) { /* Process all characters in the entry */
    uc = ld_word(dir + LfnOfs[s]);   /* Pick an LFN character */
    if (wc != 0) {
      if (i >= FF_MAX_LFN + 1) return 0; /* Buffer overflow? */
      lfnbuf[i++] = wc = uc;             /* Store it */
    } else {
      if (uc != 0xFFFF) return 0; /* Check filler */
    }
  }

  if (dir[LDIR_Ord] & LLEF &&
      wc != 0) { /* Put terminator if it is the last LFN part and not terminated */
    if (i >= FF_MAX_LFN + 1) return 0; /* Buffer overflow? */
    lfnbuf[i] = 0;
  }

  return 1; /* The part of LFN is valid */
}
#  endif

#  if !FF_FS_READONLY
/*-----------------------------------------*/
/* FAT-LFN: Create an entry of LFN entries */
/*-----------------------------------------*/

static void put_lfn(const char16_t *lfn, /* Pointer to the LFN */
                    byte           *dir, /* Pointer to the LFN entry to be created */
                    byte            ord, /* LFN order (1-20) */
                    byte            sum  /* Checksum of the corresponding SFN */
) {
  uint     i, s;
  char16_t wc;

  dir[LDIR_Chksum] = sum;    /* Set checksum */
  dir[LDIR_Attr]   = AM_LFN; /* Set attribute. LFN entry */
  dir[LDIR_Type]   = 0;
  st_word(dir + LDIR_FstClusLO, 0);

  i = (ord - 1) * 13; /* Get offset in the LFN working buffer */
  s = wc = 0;
  do {
    if (wc != 0xFFFF) wc = lfn[i++]; /* Get an effective character */
    st_word(dir + LfnOfs[s], wc);    /* Put it */
    if (wc == 0) wc = 0xFFFF;        /* Padding characters for following items */
  } while (++s < 13);
  if (wc == 0xFFFF || !lfn[i]) ord |= LLEF; /* Last LFN part is the start of LFN sequence */
  dir[LDIR_Ord] = ord;                      /* Set the LFN order */
}

#  endif /* !FF_FS_READONLY */
#endif   /* FF_USE_LFN */

#if FF_USE_LFN && !FF_FS_READONLY
/*-----------------------------------------------------------------------*/
/* FAT-LFN: Create a Numbered SFN                                        */
/*-----------------------------------------------------------------------*/

static void gen_numname(byte           *dst, /* Pointer to the buffer to store numbered SFN */
                        const byte     *src, /* Pointer to SFN in directory form */
                        const char16_t *lfn, /* Pointer to LFN */
                        uint            seq  /* Sequence number */
) {
  byte     ns[8], c;
  uint     i, j;
  char16_t wc;
  u32      sreg;

  memcpy(dst, src, 11); /* Prepare the SFN to be modified */

  if (seq >
      5) { /* In case of many collisions, generate a hash number instead of sequential number */
    sreg = seq;
    while (*lfn) { /* Create a CRC as hash value */
      wc = *lfn++;
      for (i = 0; i < 16; i++) {
        sreg   = (sreg << 1) + (wc & 1);
        wc   >>= 1;
        if (sreg & 0x10000) sreg ^= 0x11021;
      }
    }
    seq = (uint)sreg;
  }

  /* Make suffix (~ + hexadecimal) */
  i = 7;
  do {
    c    = (byte)((seq % 16) + '0');
    seq /= 16;
    if (c > '9') c += 7;
    ns[i--] = c;
  } while (i && seq);
  ns[i] = '~';

  /* Append the suffix to the SFN body */
  for (j = 0; j < i && dst[j] != ' '; j++) { /* Find the offset to append */
    if (dbc_1st(dst[j])) {                   /* To avoid DBC break up */
      if (j == i - 1) break;
      j++;
    }
  }
  do { /* Append the suffix */
    dst[j++] = (i < 8) ? ns[i++] : ' ';
  } while (j < 8);
}
#endif /* FF_USE_LFN && !FF_FS_READONLY */

#if FF_USE_LFN
/*-----------------------------------------------------------------------*/
/* FAT-LFN: Calculate checksum of an SFN entry                           */
/*-----------------------------------------------------------------------*/

static byte sum_sfn(const byte *dir /* Pointer to the SFN entry */
) {
  byte sum = 0;
  uint n   = 11;

  do {
    sum = (sum >> 1) + (sum << 7) + *dir++;
  } while (--n);
  return sum;
}

#endif /* FF_USE_LFN */

#if FF_FS_EXFAT
/*-----------------------------------------------------------------------*/
/* exFAT: Checksum                                                       */
/*-----------------------------------------------------------------------*/

static u16 xdir_sum(                /* Get checksum of the directoly entry block */
                    const byte *dir /* Directory entry block to be calculated */
) {
  uint i, szblk;
  u16  sum;

  szblk = (dir[XDIR_NumSec] + 1) * SZDIRE; /* Number of bytes of the entry block */
  for (i = sum = 0; i < szblk; i++) {
    if (i == XDIR_SetSum) { /* Skip 2-byte sum field */
      i++;
    } else {
      sum = ((sum & 1) ? 0x8000 : 0) + (sum >> 1) + dir[i];
    }
  }
  return sum;
}

static u16 xname_sum(                     /* Get check sum (to be used as hash) of the file name */
                     const char16_t *name /* File name to be calculated */
) {
  char16_t chr;
  u16      sum = 0;

  while ((chr = *name++) != 0) {
    chr = (char16_t)ff_wtoupper(chr); /* File name needs to be up-case converted */
    sum = ((sum & 1) ? 0x8000 : 0) + (sum >> 1) + (chr & 0xFF);
    sum = ((sum & 1) ? 0x8000 : 0) + (sum >> 1) + (chr >> 8);
  }
  return sum;
}

#  if !FF_FS_READONLY && FF_USE_MKFS
static u32 xsum32(          /* Returns 32-bit checksum */
                  byte dat, /* Byte to be calculated (byte-by-byte processing) */
                  u32  sum  /* Previous sum value */
) {
  sum = ((sum & 1) ? 0x80000000 : 0) + (sum >> 1) + dat;
  return sum;
}
#  endif

/*------------------------------------*/
/* exFAT: Get a directory entry block */
/*------------------------------------*/

static FRESULT
load_xdir(        /* FR_INT_ERR: invalid entry block */
          DIR *dp /* Reading directory object pointing top of the entry block to load */
) {
  FRESULT res;
  uint    i, sz_ent;
  byte   *dirb = dp->obj.fs->dirbuf; /* Pointer to the on-memory directory entry block 85+C0+C1s */

  /* Load file directory entry */
  res = move_window(dp->obj.fs, dp->sect);
  if (res != FR_OK) return res;
  if (dp->dir[XDIR_Type] != ET_FILEDIR) return FR_INT_ERR; /* Invalid order */
  memcpy(dirb + 0 * SZDIRE, dp->dir, SZDIRE);
  sz_ent = (dirb[XDIR_NumSec] + 1) * SZDIRE;
  if (sz_ent < 3 * SZDIRE || sz_ent > 19 * SZDIRE) return FR_INT_ERR;

  /* Load stream extension entry */
  res = dir_next(dp, 0);
  if (res == FR_NO_FILE) res = FR_INT_ERR; /* It cannot be */
  if (res != FR_OK) return res;
  res = move_window(dp->obj.fs, dp->sect);
  if (res != FR_OK) return res;
  if (dp->dir[XDIR_Type] != ET_STREAM) return FR_INT_ERR; /* Invalid order */
  memcpy(dirb + 1 * SZDIRE, dp->dir, SZDIRE);
  if (MAXDIRB(dirb[XDIR_NumName]) > sz_ent) return FR_INT_ERR;

  /* Load file name entries */
  i = 2 * SZDIRE; /* Name offset to load */
  do {
    res = dir_next(dp, 0);
    if (res == FR_NO_FILE) res = FR_INT_ERR; /* It cannot be */
    if (res != FR_OK) return res;
    res = move_window(dp->obj.fs, dp->sect);
    if (res != FR_OK) return res;
    if (dp->dir[XDIR_Type] != ET_FILENAME) return FR_INT_ERR; /* Invalid order */
    if (i < MAXDIRB(FF_MAX_LFN)) memcpy(dirb + i, dp->dir, SZDIRE);
  } while ((i += SZDIRE) < sz_ent);

  /* Sanity check (do it for only accessible object) */
  if (i <= MAXDIRB(FF_MAX_LFN)) {
    if (xdir_sum(dirb) != ld_word(dirb + XDIR_SetSum)) return FR_INT_ERR;
  }
  return FR_OK;
}

/*------------------------------------------------------------------*/
/* exFAT: Initialize object allocation info with loaded entry block */
/*------------------------------------------------------------------*/

static void init_alloc_info(FATFS   *fs, /* Filesystem object */
                            FFOBJID *obj /* Object allocation information to be initialized */
) {
  obj->sclust  = ld_dword(fs->dirbuf + XDIR_FstClus);  /* Start cluster */
  obj->objsize = ld_qword(fs->dirbuf + XDIR_FileSize); /* Size */
  obj->stat    = fs->dirbuf[XDIR_GenFlags] & 2;        /* Allocation status */
  obj->n_frag  = 0;                                    /* No last fragment info */
}

#  if !FF_FS_READONLY || FF_FS_RPATH != 0
/*------------------------------------------------*/
/* exFAT: Load the object's directory entry block */
/*------------------------------------------------*/

static FRESULT
load_obj_xdir(DIR *dp, /* Blank directory object to be used to access containing directory */
              const FFOBJID *obj /* Object with its containing directory information */
) {
  FRESULT res;

  /* Open object containing directory */
  dp->obj.fs      = obj->fs;
  dp->obj.sclust  = obj->c_scl;
  dp->obj.stat    = (byte)obj->c_size;
  dp->obj.objsize = obj->c_size & 0xFFFFFF00;
  dp->obj.n_frag  = 0;
  dp->blk_ofs     = obj->c_ofs;

  res = dir_sdi(dp, dp->blk_ofs); /* Goto object's entry block */
  if (res == FR_OK) { res = load_xdir(dp); /* Load the object's entry block */ }
  return res;
}
#  endif

#  if !FF_FS_READONLY
/*----------------------------------------*/
/* exFAT: Store the directory entry block */
/*----------------------------------------*/

static FRESULT store_xdir(DIR *dp /* Pointer to the directory object */
) {
  FRESULT res;
  uint    nent;
  byte   *dirb = dp->obj.fs->dirbuf; /* Pointer to the directory entry block 85+C0+C1s */

  /* Create set sum */
  st_word(dirb + XDIR_SetSum, xdir_sum(dirb));
  nent = dirb[XDIR_NumSec] + 1;

  /* Store the directory entry block to the directory */
  res = dir_sdi(dp, dp->blk_ofs);
  while (res == FR_OK) {
    res = move_window(dp->obj.fs, dp->sect);
    if (res != FR_OK) break;
    memcpy(dp->dir, dirb, SZDIRE);
    dp->obj.fs->wflag = 1;
    if (--nent == 0) break;
    dirb += SZDIRE;
    res   = dir_next(dp, 0);
  }
  return (res == FR_OK || res == FR_DISK_ERR) ? res : FR_INT_ERR;
}

/*-------------------------------------------*/
/* exFAT: Create a new directory entry block */
/*-------------------------------------------*/

static void create_xdir(byte           *dirb, /* Pointer to the directory entry block buffer */
                        const char16_t *lfn   /* Pointer to the object name */
) {
  uint     i;
  byte     nc1, nlen;
  char16_t wc;

  /* Create file-directory and stream-extension entry */
  memset(dirb, 0, 2 * SZDIRE);
  dirb[0 * SZDIRE + XDIR_Type] = ET_FILEDIR;
  dirb[1 * SZDIRE + XDIR_Type] = ET_STREAM;

  /* Create file-name entries */
  i    = SZDIRE * 2; /* Top of file_name entries */
  nlen = nc1 = 0;
  wc         = 1;
  do {
    dirb[i++] = ET_FILENAME;
    dirb[i++] = 0;
    do {                                            /* Fill name field */
      if (wc != 0 && (wc = lfn[nlen]) != 0) nlen++; /* Get a character if exist */
      st_word(dirb + i, wc);                        /* Store it */
      i += 2;
    } while (i % SZDIRE != 0);
    nc1++;
  } while (lfn[nlen]); /* Fill next entry if any char follows */

  dirb[XDIR_NumName] = nlen;                     /* Set name length */
  dirb[XDIR_NumSec]  = 1 + nc1;                  /* Set secondary count (C0 + C1s) */
  st_word(dirb + XDIR_NameHash, xname_sum(lfn)); /* Set name hash */
}

#  endif /* !FF_FS_READONLY */
#endif   /* FF_FS_EXFAT */

#if FF_FS_MINIMIZE <= 1 || FF_FS_RPATH >= 2 || FF_USE_LABEL || FF_FS_EXFAT
/*-----------------------------------------------------------------------*/
/* Read an object from the directory                                     */
/*-----------------------------------------------------------------------*/

#  define DIR_READ_FILE(dp)  dir_read(dp, 0)
#  define DIR_READ_LABEL(dp) dir_read(dp, 1)

static FRESULT dir_read(DIR *dp, /* Pointer to the directory object */
                        int  vol /* Filtered by 0:file/directory or 1:volume label */
) {
  FRESULT res = FR_NO_FILE;
  FATFS  *fs  = dp->obj.fs;
  byte    attr, b;
#  if FF_USE_LFN
  byte ord = 0xFF, sum = 0xFF;
#  endif

  while (dp->sect) {
    res = move_window(fs, dp->sect);
    if (res != FR_OK) break;
    b = dp->dir[DIR_Name]; /* Test for the entry type */
    if (b == 0) {
      res = FR_NO_FILE;
      break; /* Reached to end of the directory */
    }
#  if FF_FS_EXFAT
    if (fs->fs_type == FS_EXFAT) { /* On the exFAT volume */
      if (FF_USE_LABEL && vol) {
        if (b == ET_VLABEL) break; /* Volume label entry? */
      } else {
        if (b == ET_FILEDIR) {         /* Start of the file entry block? */
          dp->blk_ofs = dp->dptr;      /* Get location of the block */
          res         = load_xdir(dp); /* Load the entry block */
          if (res == FR_OK) { dp->obj.attr = fs->dirbuf[XDIR_Attr] & AM_MASK; /* Get attribute */ }
          break;
        }
      }
    } else
#  endif
    {                                                    /* On the FAT/FAT32 volume */
      dp->obj.attr = attr = dp->dir[DIR_Attr] & AM_MASK; /* Get attribute */
#  if FF_USE_LFN                                         /* LFN configuration */
      if (b == DDEM || b == '.' ||
          (int)((attr & ~AM_ARC) == AM_VOL) != vol) { /* An entry without valid data */
        ord = 0xFF;
      } else {
        if (attr == AM_LFN) { /* An LFN entry is found */
          if (b & LLEF) {     /* Is it start of an LFN sequence? */
            sum          = dp->dir[LDIR_Chksum];
            b           &= (byte)~LLEF;
            ord          = b;
            dp->blk_ofs  = dp->dptr;
          }
          /* Check LFN validity and capture it */
          ord = (b == ord && sum == dp->dir[LDIR_Chksum] && pick_lfn(fs->lfnbuf, dp->dir)) ? ord - 1
                                                                                           : 0xFF;
        } else {                                     /* An SFN entry is found */
          if (ord != 0 || sum != sum_sfn(dp->dir)) { /* Is there a valid LFN? */
            dp->blk_ofs = 0xFFFFFFFF;                /* It has no LFN. */
          }
          break;
        }
      }
#  else /* Non LFN configuration */
      if (b != DDEM && b != '.' && attr != AM_LFN &&
          (int)((attr & ~AM_ARC) == AM_VOL) == vol) { /* Is it a valid entry? */
        break;
      }
#  endif
    }
    res = dir_next(dp, 0); /* Next entry */
    if (res != FR_OK) break;
  }

  if (res != FR_OK) dp->sect = 0; /* Terminate the read operation on error or EOT */
  return res;
}

#endif /* FF_FS_MINIMIZE <= 1 || FF_USE_LABEL || FF_FS_RPATH >= 2 */

/*-----------------------------------------------------------------------*/
/* Directory handling - Find an object in the directory                  */
/*-----------------------------------------------------------------------*/

static FRESULT dir_find(        /* FR_OK(0):succeeded, !=0:error */
                        DIR *dp /* Pointer to the directory object with the file name */
) {
  FRESULT res;
  FATFS  *fs = dp->obj.fs;
  byte    c;
#if FF_USE_LFN
  byte a, ord, sum;
#endif

  res = dir_sdi(dp, 0); /* Rewind directory object */
  if (res != FR_OK) return res;
#if FF_FS_EXFAT
  if (fs->fs_type == FS_EXFAT) { /* On the exFAT volume */
    byte nc;
    uint di, ni;
    u16  hash = xname_sum(fs->lfnbuf); /* Hash value of the name to find */

    while ((res = DIR_READ_FILE(dp)) == FR_OK) { /* Read an item */
#  if FF_MAX_LFN < 255
      if (fs->dirbuf[XDIR_NumName] > FF_MAX_LFN)
        continue; /* Skip comparison if inaccessible object name */
#  endif
      if (ld_word(fs->dirbuf + XDIR_NameHash) != hash)
        continue; /* Skip comparison if hash mismatched */
      for (nc = fs->dirbuf[XDIR_NumName], di = SZDIRE * 2, ni = 0; nc;
           nc--, di += 2, ni++) { /* Compare the name */
        if ((di % SZDIRE) == 0) di += 2;
        if (ff_wtoupper(ld_word(fs->dirbuf + di)) != ff_wtoupper(fs->lfnbuf[ni])) break;
      }
      if (nc == 0 && !fs->lfnbuf[ni]) break; /* Name matched? */
    }
    return res;
  }
#endif
  /* On the FAT/FAT32 volume */
#if FF_USE_LFN
  ord = sum   = 0xFF;
  dp->blk_ofs = 0xFFFFFFFF; /* Reset LFN sequence */
#endif
  do {
    res = move_window(fs, dp->sect);
    if (res != FR_OK) break;
    c = dp->dir[DIR_Name];
    if (c == 0) {
      res = FR_NO_FILE;
      break;
    }          /* Reached to end of table */
#if FF_USE_LFN /* LFN configuration */
    dp->obj.attr = a = dp->dir[DIR_Attr] & AM_MASK;
    if (c == DDEM || ((a & AM_VOL) && a != AM_LFN)) { /* An entry without valid data */
      ord         = 0xFF;
      dp->blk_ofs = 0xFFFFFFFF; /* Reset LFN sequence */
    } else {
      if (a == AM_LFN) { /* An LFN entry is found */
        if (!(dp->fn[NSFLAG] & NS_NOLFN)) {
          if (c & LLEF) { /* Is it start of LFN sequence? */
            sum          = dp->dir[LDIR_Chksum];
            c           &= (byte)~LLEF;
            ord          = c;        /* LFN start order */
            dp->blk_ofs  = dp->dptr; /* Start offset of LFN */
          }
          /* Check validity of the LFN entry and compare it with given name */
          ord = (c == ord && sum == dp->dir[LDIR_Chksum] && cmp_lfn(fs->lfnbuf, dp->dir)) ? ord - 1
                                                                                          : 0xFF;
        }
      } else {                                          /* An SFN entry is found */
        if (ord == 0 && sum == sum_sfn(dp->dir)) break; /* LFN matched? */
        if (!(dp->fn[NSFLAG] & NS_LOSS) && !memcmp(dp->dir, dp->fn, 11)) break; /* SFN matched? */
        ord         = 0xFF;
        dp->blk_ofs = 0xFFFFFFFF; /* Reset LFN sequence */
      }
    }
#else /* Non LFN configuration */
    dp->obj.attr = dp->dir[DIR_Attr] & AM_MASK;
    if (!(dp->dir[DIR_Attr] & AM_VOL) && !memcmp(dp->dir, dp->fn, 11))
      break; /* Is it a valid entry? */
#endif
    res = dir_next(dp, 0); /* Next entry */
  } while (res == FR_OK);

  return res;
}

#if !FF_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Register an object to the directory                                   */
/*-----------------------------------------------------------------------*/

static FRESULT
dir_register(/* FR_OK:succeeded, FR_DENIED:no free entry or too many SFN collision, FR_DISK_ERR:disk error */
             DIR *dp /* Target directory with object name to be created */
) {
  FRESULT res;
  FATFS  *fs = dp->obj.fs;
#  if FF_USE_LFN /* LFN configuration */
  uint n, len, n_ent;
  byte sn[12], sum;

  if (dp->fn[NSFLAG] & (NS_DOT | NS_NONAME)) return FR_INVALID_NAME; /* Check name validity */
  for (len = 0; fs->lfnbuf[len]; len++)
    ; /* Get lfn length */

#    if FF_FS_EXFAT
  if (fs->fs_type == FS_EXFAT) {  /* On the exFAT volume */
    n_ent = (len + 14) / 15 + 2;  /* Number of entries to allocate (85+C0+C1s) */
    res   = dir_alloc(dp, n_ent); /* Allocate directory entries */
    if (res != FR_OK) return res;
    dp->blk_ofs = dp->dptr - SZDIRE * (n_ent - 1); /* Set the allocated entry block offset */

    if (dp->obj.stat & 4) { /* Has the directory been stretched by new allocation? */
      dp->obj.stat &= ~4;
      res           = fill_first_frag(&dp->obj); /* Fill the first fragment on the FAT if needed */
      if (res != FR_OK) return res;
      res = fill_last_frag(&dp->obj, dp->clust,
                           0xFFFFFFFF); /* Fill the last fragment on the FAT if needed */
      if (res != FR_OK) return res;
      if (dp->obj.sclust != 0) { /* Is it a sub-directory? */
        DIR dj;

        res = load_obj_xdir(&dj, &dp->obj); /* Load the object status */
        if (res != FR_OK) return res;
        dp->obj.objsize +=
            (u32)fs->csize * SS(fs); /* Increase the directory size by cluster size */
        st_qword(fs->dirbuf + XDIR_FileSize, dp->obj.objsize);
        st_qword(fs->dirbuf + XDIR_ValidFileSize, dp->obj.objsize);
        fs->dirbuf[XDIR_GenFlags] = dp->obj.stat | 1; /* Update the allocation status */
        res                       = store_xdir(&dj);  /* Store the object status */
        if (res != FR_OK) return res;
      }
    }

    create_xdir(fs->dirbuf, fs->lfnbuf); /* Create on-memory directory block to be written later */
    return FR_OK;
  }
#    endif
  /* On the FAT/FAT32 volume */
  memcpy(sn, dp->fn, 12);
  if (sn[NSFLAG] & NS_LOSS) {  /* When LFN is out of 8.3 format, generate a numbered name */
    dp->fn[NSFLAG] = NS_NOLFN; /* Find only SFN */
    for (n = 1; n < 100; n++) {
      gen_numname(dp->fn, sn, fs->lfnbuf, n); /* Generate a numbered name */
      res = dir_find(dp);                     /* Check if the name collides with existing SFN */
      if (res != FR_OK) break;
    }
    if (n == 100) return FR_DENIED;    /* Abort if too many collisions */
    if (res != FR_NO_FILE) return res; /* Abort if the result is other than 'not collided' */
    dp->fn[NSFLAG] = sn[NSFLAG];
  }

  /* Create an SFN with/without LFNs. */
  n_ent = (sn[NSFLAG] & NS_LFN) ? (len + 12) / 13 + 1 : 1; /* Number of entries to allocate */
  res   = dir_alloc(dp, n_ent);                            /* Allocate entries */
  if (res == FR_OK && --n_ent) {                           /* Set LFN entry if needed */
    res = dir_sdi(dp, dp->dptr - n_ent * SZDIRE);
    if (res == FR_OK) {
      sum = sum_sfn(dp->fn); /* Checksum value of the SFN tied to the LFN */
      do {                   /* Store LFN entries in bottom first */
        res = move_window(fs, dp->sect);
        if (res != FR_OK) break;
        put_lfn(fs->lfnbuf, dp->dir, (byte)n_ent, sum);
        fs->wflag = 1;
        res       = dir_next(dp, 0); /* Next entry */
      } while (res == FR_OK && --n_ent);
    }
  }

#  else /* Non LFN configuration */
  res = dir_alloc(dp, 1); /* Allocate an entry for SFN */

#  endif

  /* Set SFN entry */
  if (res == FR_OK) {
    res = move_window(fs, dp->sect);
    if (res == FR_OK) {
      memset(dp->dir, 0, SZDIRE);             /* Clean the entry */
      memcpy(dp->dir + DIR_Name, dp->fn, 11); /* Put SFN */
#  if FF_USE_LFN
      dp->dir[DIR_NTres] = dp->fn[NSFLAG] & (NS_BODY | NS_EXT); /* Put NT flag */
#  endif
      fs->wflag = 1;
    }
  }

  return res;
}

#endif /* !FF_FS_READONLY */

#if !FF_FS_READONLY && FF_FS_MINIMIZE == 0
/*-----------------------------------------------------------------------*/
/* Remove an object from the directory                                   */
/*-----------------------------------------------------------------------*/

static FRESULT dir_remove(        /* FR_OK:Succeeded, FR_DISK_ERR:A disk error */
                          DIR *dp /* Directory object pointing the entry to be removed */
) {
  FRESULT res;
  FATFS  *fs = dp->obj.fs;
#  if FF_USE_LFN /* LFN configuration */
  u32 last = dp->dptr;

  res = (dp->blk_ofs == 0xFFFFFFFF)
            ? FR_OK
            : dir_sdi(dp, dp->blk_ofs); /* Goto top of the entry block if LFN is exist */
  if (res == FR_OK) {
    do {
      res = move_window(fs, dp->sect);
      if (res != FR_OK) break;
      if (FF_FS_EXFAT && fs->fs_type == FS_EXFAT) { /* On the exFAT volume */
        dp->dir[XDIR_Type] &= 0x7F;                 /* Clear the entry InUse flag. */
      } else {                                      /* On the FAT/FAT32 volume */
        dp->dir[DIR_Name] = DDEM;                   /* Mark the entry 'deleted'. */
      }
      fs->wflag = 1;
      if (dp->dptr >= last)
        break; /* If reached last entry then all entries of the object has been deleted. */
      res = dir_next(dp, 0); /* Next entry */
    } while (res == FR_OK);
    if (res == FR_NO_FILE) res = FR_INT_ERR;
  }
#  else /* Non LFN configuration */

  res = move_window(fs, dp->sect);
  if (res == FR_OK) {
    dp->dir[DIR_Name] = DDEM; /* Mark the entry 'deleted'.*/
    fs->wflag         = 1;
  }
#  endif

  return res;
}

#endif /* !FF_FS_READONLY && FF_FS_MINIMIZE == 0 */

#if FF_FS_MINIMIZE <= 1 || FF_FS_RPATH >= 2
/*-----------------------------------------------------------------------*/
/* Get file information from directory entry                             */
/*-----------------------------------------------------------------------*/

static void get_fileinfo(DIR     *dp, /* Pointer to the directory object */
                         FILINFO *fno /* Pointer to the file information to be filled */
) {
  uint si, di;
#  if FF_USE_LFN
  byte     lcf;
  char16_t wc, hs;
  FATFS   *fs = dp->obj.fs;
  uint     nw;
#  else
  TCHAR c;
#  endif

  fno->fname[0] = 0;         /* Invaidate file info */
  if (dp->sect == 0) return; /* Exit if read pointer has reached end of directory */

#  if FF_USE_LFN /* LFN configuration */
#    if FF_FS_EXFAT
  if (fs->fs_type == FS_EXFAT) { /* exFAT volume */
    uint nc = 0;

    si = SZDIRE * 2;
    di = 0; /* 1st C1 entry in the entry block */
    hs = 0;
    while (nc < fs->dirbuf[XDIR_NumName]) {
      if (si >= MAXDIRB(FF_MAX_LFN)) { /* Truncated directory block? */
        di = 0;
        break;
      }
      if ((si % SZDIRE) == 0) si += 2; /* Skip entry type field */
      wc  = ld_word(fs->dirbuf + si);
      si += 2;
      nc++;                             /* Get a character */
      if (hs == 0 && IsSurrogate(wc)) { /* Is it a surrogate? */
        hs = wc;
        continue; /* Get low surrogate */
      }
      nw = put_utf((u32)hs << 16 | wc, &fno->fname[di],
                   FF_LFN_BUF - di); /* Store it in API encoding */
      if (nw == 0) {                 /* Buffer overflow or wrong char? */
        di = 0;
        break;
      }
      di += nw;
      hs  = 0;
    }
    if (hs != 0) di = 0;                  /* Broken surrogate pair? */
    if (di == 0) fno->fname[di++] = '\?'; /* Inaccessible object name? */
    fno->fname[di]  = 0;                  /* Terminate the name */
    fno->altname[0] = 0;                  /* exFAT does not support SFN */

    fno->fattrib = fs->dirbuf[XDIR_Attr] & AM_MASKX; /* Attribute */
    fno->fsize   = (fno->fattrib & AM_DIR) ? 0 : ld_qword(fs->dirbuf + XDIR_FileSize); /* Size */
    fno->ftime   = ld_word(fs->dirbuf + XDIR_ModTime + 0);                             /* Time */
    fno->fdate   = ld_word(fs->dirbuf + XDIR_ModTime + 2);                             /* Date */
    return;
  } else
#    endif
  {                                  /* FAT/FAT32 volume */
    if (dp->blk_ofs != 0xFFFFFFFF) { /* Get LFN if available */
      si = di = 0;
      hs      = 0;
      while (fs->lfnbuf[si] != 0) {
        wc = fs->lfnbuf[si++];            /* Get an LFN character (UTF-16) */
        if (hs == 0 && IsSurrogate(wc)) { /* Is it a surrogate? */
          hs = wc;
          continue; /* Get low surrogate */
        }
        nw = put_utf((u32)hs << 16 | wc, &fno->fname[di],
                     FF_LFN_BUF - di); /* Store it in API encoding */
        if (nw == 0) {                 /* Buffer overflow or wrong char? */
          di = 0;
          break;
        }
        di += nw;
        hs  = 0;
      }
      if (hs != 0) di = 0; /* Broken surrogate pair? */
      fno->fname[di] = 0;  /* Terminate the LFN (null string means LFN is invalid) */
    }
  }

  si = di = 0;
  while (si < 11) {                                           /* Get SFN from SFN entry */
    wc = dp->dir[si++];                                       /* Get a char */
    if (wc == ' ') continue;                                  /* Skip padding spaces */
    if (wc == RDDEM) wc = DDEM;                               /* Restore replaced DDEM character */
    if (si == 9 && di < FF_SFN_BUF) fno->altname[di++] = '.'; /* Insert a . if extension is exist */
#    if FF_LFN_UNICODE >= 1                                   /* Unicode output */
    if (dbc_1st((byte)wc) && si != 8 && si != 11 &&
        dbc_2nd(dp->dir[si])) { /* Make a DBC if needed */
      wc = wc << 8 | dp->dir[si++];
    }
    wc = ff_oem2uni(wc, CODEPAGE); /* ANSI/OEM -> Unicode */
    if (wc == 0) {                 /* Wrong char in the current code page? */
      di = 0;
      break;
    }
    nw = put_utf(wc, &fno->altname[di], FF_SFN_BUF - di); /* Store it in API encoding */
    if (nw == 0) {                                        /* Buffer overflow? */
      di = 0;
      break;
    }
    di += nw;
#    else /* ANSI/OEM output */
    fno->altname[di++] = (TCHAR)wc; /* Store it without any conversion */
#    endif
  }
  fno->altname[di] = 0; /* Terminate the SFN  (null string means SFN is invalid) */

  if (fno->fname[0] == 0) { /* If LFN is invalid, altname[] needs to be copied to fname[] */
    if (di == 0) {          /* If LFN and SFN both are invalid, this object is inaccessible */
      fno->fname[di++] = '\?';
    } else {
      for (si = di = 0, lcf = NS_BODY; fno->altname[si];
           si++, di++) { /* Copy altname[] to fname[] with case information */
        wc = (char16_t)fno->altname[si];
        if (wc == '.') lcf = NS_EXT;
        if (IsUpper(wc) && (dp->dir[DIR_NTres] & lcf)) wc += 0x20;
        fno->fname[di] = (TCHAR)wc;
      }
    }
    fno->fname[di] = 0; /* Terminate the LFN */
    if (!dp->dir[DIR_NTres])
      fno->altname[0] = 0; /* Altname is not needed if neither LFN nor case info is exist. */
  }

#  else /* Non-LFN configuration */
  si = di = 0;
  while (si < 11) { /* Copy name body and extension */
    c = (TCHAR)dp->dir[si++];
    if (c == ' ') continue;              /* Skip padding spaces */
    if (c == RDDEM) c = DDEM;            /* Restore replaced DDEM character */
    if (si == 9) fno->fname[di++] = '.'; /* Insert a . if extension is exist */
    fno->fname[di++] = c;
  }
  fno->fname[di] = 0; /* Terminate the SFN */
#  endif

  fno->fattrib = dp->dir[DIR_Attr] & AM_MASK;        /* Attribute */
  fno->fsize   = ld_dword(dp->dir + DIR_FileSize);   /* Size */
  fno->ftime   = ld_word(dp->dir + DIR_ModTime + 0); /* Time */
  fno->fdate   = ld_word(dp->dir + DIR_ModTime + 2); /* Date */
}

#endif /* FF_FS_MINIMIZE <= 1 || FF_FS_RPATH >= 2 */

#if FF_USE_FIND && FF_FS_MINIMIZE <= 1
/*-----------------------------------------------------------------------*/
/* Pattern matching                                                      */
/*-----------------------------------------------------------------------*/

#  define FIND_RECURS 4 /* Maximum number of wildcard terms in the pattern to limit recursion */

static u32 get_achar(                  /* Get a character and advance ptr */
                     const TCHAR **ptr /* Pointer to pointer to the ANSI/OEM or Unicode string */
) {
  u32 chr;

#  if FF_USE_LFN && FF_LFN_UNICODE >= 1 /* Unicode input */
  chr = tchar2uni(ptr);
  if (chr == 0xFFFFFFFF) chr = 0; /* Wrong UTF encoding is recognized as end of the string */
  chr = ff_wtoupper(chr);

#  else /* ANSI/OEM input */
  chr = (byte) * (*ptr)++;       /* Get a byte */
  if (IsLower(chr)) chr -= 0x20; /* To upper ASCII char */
#    if FF_CODE_PAGE == 0
  if (ExCvt && chr >= 0x80) chr = ExCvt[chr - 0x80]; /* To upper SBCS extended char */
#    elif FF_CODE_PAGE < 900
  if (chr >= 0x80) chr = ExCvt[chr - 0x80]; /* To upper SBCS extended char */
#    endif
#    if FF_CODE_PAGE == 0 || FF_CODE_PAGE >= 900
  if (dbc_1st((byte)chr)) { /* Get DBC 2nd byte if needed */
    chr = dbc_2nd((byte) * *ptr) ? chr << 8 | (byte) * (*ptr)++ : 0;
  }
#    endif

#  endif
  return chr;
}

static int
pattern_match(                  /* 0:mismatched, 1:matched */
              const TCHAR *pat, /* Matching pattern */
              const TCHAR *nam, /* String to be tested */
              uint skip, /* Number of pre-skip chars (number of ?s, b8:infinite (* specified)) */
              uint recur /* Recursion count */
) {
  const TCHAR *pptr;
  const TCHAR *nptr;
  u32          pchr, nchr;
  uint         sk;

  while ((skip & 0xFF) != 0) {      /* Pre-skip name chars */
    if (!get_achar(&nam)) return 0; /* Branch mismatched if less name chars */
    skip--;
  }
  if (*pat == 0 && skip) return 1; /* Matched? (short circuit) */

  do {
    pptr = pat;
    nptr = nam; /* Top of pattern and name to match */
    for (;;) {
      if (*pptr == '\?' || *pptr == '*') { /* Wildcard term? */
        if (recur == 0) return 0;          /* Too many wildcard terms? */
        sk = 0;
        do { /* Analyze the wildcard term */
          if (*pptr++ == '\?') {
            sk++;
          } else {
            sk |= 0x100;
          }
        } while (*pptr == '\?' || *pptr == '*');
        if (pattern_match(pptr, nptr, sk, recur - 1))
          return 1; /* Test new branch (recursive call) */
        nchr = *nptr;
        break; /* Branch mismatched */
      }
      pchr = get_achar(&pptr); /* Get a pattern char */
      nchr = get_achar(&nptr); /* Get a name char */
      if (pchr != nchr) break; /* Branch mismatched? */
      if (pchr == 0) return 1; /* Branch matched? (matched at end of both strings) */
    }
    get_achar(&nam);      /* nam++ */
  } while (skip && nchr); /* Retry until end of name if infinite search is specified */

  return 0;
}

#endif /* FF_USE_FIND && FF_FS_MINIMIZE <= 1 */

/*-----------------------------------------------------------------------*/
/* Pick a top segment and create the object name in directory form       */
/*-----------------------------------------------------------------------*/

static FRESULT
create_name(                   /* FR_OK: successful, FR_INVALID_NAME: could not create */
            DIR          *dp,  /* Pointer to the directory object */
            const TCHAR **path /* Pointer to pointer to the segment in the path string */
) {
#if FF_USE_LFN /* LFN configuration */
  byte         b, cf;
  char16_t     wc;
  char16_t    *lfn;
  const TCHAR *p;
  u32          uc;
  uint         i, ni, si, di;

  /* Create LFN into LFN working buffer */
  p   = *path;
  lfn = dp->obj.fs->lfnbuf;
  di  = 0;
  for (;;) {
    uc = tchar2uni(&p);                                  /* Get a character */
    if (uc == 0xFFFFFFFF) return FR_INVALID_NAME;        /* Invalid code or UTF decode error */
    if (uc >= 0x10000) lfn[di++] = (char16_t)(uc >> 16); /* Store high surrogate if needed */
    wc = (char16_t)uc;
    if (wc < ' ' || IsSeparator(wc)) break; /* Break if end of the path or a separator is found */
    if (wc < 0x80 && strchr("*:<>|\"\?\x7F", (int)wc))
      return FR_INVALID_NAME;                     /* Reject illegal characters for LFN */
    if (di >= FF_MAX_LFN) return FR_INVALID_NAME; /* Reject too long name */
    lfn[di++] = wc;                               /* Store the Unicode character */
  }
  if (wc < ' ') { /* Stopped at end of the path? */
    cf = NS_LAST; /* Last segment */
  } else {        /* Stopped at a separator */
    while (IsSeparator(*p))
      p++;                              /* Skip duplicated separators if exist */
    cf = 0;                             /* Next segment may follow */
    if (IsTerminator(*p)) cf = NS_LAST; /* Ignore terminating separator */
  }
  *path = p; /* Return pointer to the next segment */

#  if FF_FS_RPATH != 0
  if ((di == 1 && lfn[di - 1] == '.') ||
      (di == 2 && lfn[di - 1] == '.' && lfn[di - 2] == '.')) { /* Is this segment a dot name? */
    lfn[di] = 0;
    for (i = 0; i < 11; i++) { /* Create dot name for SFN entry */
      dp->fn[i] = (i < di) ? '.' : ' ';
    }
    dp->fn[i] = cf | NS_DOT; /* This is a dot entry */
    return FR_OK;
  }
#  endif
  while (di) { /* Snip off trailing spaces and dots if exist */
    wc = lfn[di - 1];
    if (wc != ' ' && wc != '.') break;
    di--;
  }
  lfn[di] = 0;                         /* LFN is created into the working buffer */
  if (di == 0) return FR_INVALID_NAME; /* Reject null name */

  /* Create SFN in directory form */
  for (si = 0; lfn[si] == ' '; si++)
    ;                                                   /* Remove leading spaces */
  if (si > 0 || lfn[si] == '.') cf |= NS_LOSS | NS_LFN; /* Is there any leading space or dot? */
  while (di > 0 && lfn[di - 1] != '.')
    di--; /* Find last dot (di<=si: no extension) */

  memset(dp->fn, ' ', 11);
  i = b = 0;
  ni    = 8;
  for (;;) {
    wc = lfn[si++];                             /* Get an LFN character */
    if (wc == 0) break;                         /* Break on end of the LFN */
    if (wc == ' ' || (wc == '.' && si != di)) { /* Remove embedded spaces and dots */
      cf |= NS_LOSS | NS_LFN;
      continue;
    }

    if (i >= ni || si == di) { /* End of field? */
      if (ni == 11) {          /* Name extension overflow? */
        cf |= NS_LOSS | NS_LFN;
        break;
      }
      if (si != di) cf |= NS_LOSS | NS_LFN; /* Name body overflow? */
      if (si > di) break;                   /* No name extension? */
      si   = di;
      i    = 8;
      ni   = 11;
      b  <<= 2; /* Enter name extension */
      continue;
    }

    if (wc >= 0x80) { /* Is this an extended character? */
      cf |= NS_LFN;   /* LFN entry needs to be created */
#  if FF_CODE_PAGE == 0
      if (ExCvt) {                                  /* In SBCS cfg */
        wc = ff_uni2oem(wc, CODEPAGE);              /* Unicode ==> ANSI/OEM code */
        if (wc & 0x80) wc = ExCvt[wc & 0x7F];       /* Convert extended character to upper (SBCS) */
      } else {                                      /* In DBCS cfg */
        wc = ff_uni2oem(ff_wtoupper(wc), CODEPAGE); /* Unicode ==> Up-convert ==> ANSI/OEM code */
      }
#  elif FF_CODE_PAGE < 900 /* In SBCS cfg */
      wc = ff_uni2oem(wc, CODEPAGE);        /* Unicode ==> ANSI/OEM code */
      if (wc & 0x80) wc = ExCvt[wc & 0x7F]; /* Convert extended character to upper (SBCS) */
#  else                    /* In DBCS cfg */
      wc = ff_uni2oem(ff_wtoupper(wc), CODEPAGE); /* Unicode ==> Up-convert ==> ANSI/OEM code */
#  endif
    }

    if (wc >= 0x100) {   /* Is this a DBC? */
      if (i >= ni - 1) { /* Field overflow? */
        cf |= NS_LOSS | NS_LFN;
        i   = ni;
        continue; /* Next field */
      }
      dp->fn[i++] = (byte)(wc >> 8);              /* Put 1st byte */
    } else {                                      /* SBC */
      if (wc == 0 || strchr("+,;=[]", (int)wc)) { /* Replace illegal characters for SFN */
        wc  = '_';
        cf |= NS_LOSS | NS_LFN; /* Lossy conversion */
      } else {
        if (IsUpper(wc)) { /* ASCII upper case? */
          b |= 2;
        }
        if (IsLower(wc)) { /* ASCII lower case? */
          b  |= 1;
          wc -= 0x20;
        }
      }
    }
    dp->fn[i++] = (byte)wc;
  }

  if (dp->fn[0] == DDEM)
    dp->fn[0] = RDDEM; /* If the first character collides with DDEM, replace it with RDDEM */

  if (ni == 8) b <<= 2; /* Shift capital flags if no extension */
  if ((b & 0x0C) == 0x0C || (b & 0x03) == 0x03)
    cf |= NS_LFN; /* LFN entry needs to be created if composite capitals */
  if (!(cf &
        NS_LFN)) { /* When LFN is in 8.3 format without extended character, NT flags are created */
    if (b & 0x01) cf |= NS_EXT;  /* NT flag (Extension has small capital letters only) */
    if (b & 0x04) cf |= NS_BODY; /* NT flag (Body has small capital letters only) */
  }

  dp->fn[NSFLAG] = cf; /* SFN is created into dp->fn[] */

  return FR_OK;

#else /* FF_USE_LFN : Non-LFN configuration */
  byte        c, d;
  byte       *sfn;
  uint        ni, si, i;
  const char *p;

  /* Create file name in directory form */
  p   = *path;
  sfn = dp->fn;
  memset(sfn, ' ', 11);
  si = i = 0;
  ni     = 8;
#  if FF_FS_RPATH != 0
  if (p[si] == '.') { /* Is this a dot entry? */
    for (;;) {
      c = (byte)p[si++];
      if (c != '.' || si >= 3) break;
      sfn[i++] = c;
    }
    if (!IsSeparator(c) && c > ' ') return FR_INVALID_NAME;
    *path = p + si; /* Return pointer to the next segment */
    sfn[NSFLAG] =
        (c <= ' ') ? NS_LAST | NS_DOT : NS_DOT; /* Set last segment flag if end of the path */
    return FR_OK;
  }
#  endif
  for (;;) {
    c = (byte)p[si++];    /* Get a byte */
    if (c <= ' ') break;  /* Break if end of the path name */
    if (IsSeparator(c)) { /* Break if a separator is found */
      while (IsSeparator(p[si]))
        si++; /* Skip duplicated separator if exist */
      break;
    }
    if (c == '.' || i >= ni) {                          /* End of body or field overflow? */
      if (ni == 11 || c != '.') return FR_INVALID_NAME; /* Field overflow or invalid dot? */
      i  = 8;
      ni = 11; /* Enter file extension field */
      continue;
    }
#  if FF_CODE_PAGE == 0
    if (ExCvt && c >= 0x80) { /* Is SBC extended character? */
      c = ExCvt[c & 0x7F];    /* To upper SBC extended character */
    }
#  elif FF_CODE_PAGE < 900
    if (c >= 0x80) {       /* Is SBC extended character? */
      c = ExCvt[c & 0x7F]; /* To upper SBC extended character */
    }
#  endif
    if (dbc_1st(c)) {                                         /* Check if it is a DBC 1st byte */
      d = (byte)p[si++];                                      /* Get 2nd byte */
      if (!dbc_2nd(d) || i >= ni - 1) return FR_INVALID_NAME; /* Reject invalid DBC */
      sfn[i++] = c;
      sfn[i++] = d;
    } else { /* SBC */
      if (strchr("*+,:;<=>[]|\"\?\x7F", (int)c))
        return FR_INVALID_NAME;  /* Reject illegal chrs for SFN */
      if (IsLower(c)) c -= 0x20; /* To upper */
      sfn[i++] = c;
    }
  }
  *path = &p[si];                     /* Return pointer to the next segment */
  if (i == 0) return FR_INVALID_NAME; /* Reject nul string */

  if (sfn[0] == DDEM)
    sfn[0] = RDDEM; /* If the first character collides with DDEM, replace it with RDDEM */
  sfn[NSFLAG] =
      (c <= ' ' || p[si] <= ' ') ? NS_LAST : 0; /* Set last segment flag if end of the path */

  return FR_OK;
#endif /* FF_USE_LFN */
}

/*-----------------------------------------------------------------------*/
/* Follow a file path                                                    */
/*-----------------------------------------------------------------------*/

static FRESULT follow_path(         /* FR_OK(0): successful, !=0: error code */
                           DIR *dp, /* Directory object to return last directory and found object */
                           const TCHAR *path /* Full-path string to find a file or directory */
) {
  FRESULT res;
  byte    ns;
  FATFS  *fs = dp->obj.fs;

#if FF_FS_RPATH != 0
  if (!IsSeparator(*path) &&
      (FF_STR_VOLUME_ID != 2 || !IsTerminator(*path))) { /* Without heading separator */
    dp->obj.sclust = fs->cdir;                           /* Start at the current directory */
  } else
#endif
  { /* With heading separator */
    while (IsSeparator(*path))
      path++;           /* Strip separators */
    dp->obj.sclust = 0; /* Start from the root directory */
  }
#if FF_FS_EXFAT
  dp->obj.n_frag = 0; /* Invalidate last fragment counter of the object */
#  if FF_FS_RPATH != 0
  if (fs->fs_type == FS_EXFAT && dp->obj.sclust) { /* exFAT: Retrieve the sub-directory's status */
    DIR dj;

    dp->obj.c_scl  = fs->cdc_scl;
    dp->obj.c_size = fs->cdc_size;
    dp->obj.c_ofs  = fs->cdc_ofs;
    res            = load_obj_xdir(&dj, &dp->obj);
    if (res != FR_OK) return res;
    dp->obj.objsize = ld_dword(fs->dirbuf + XDIR_FileSize);
    dp->obj.stat    = fs->dirbuf[XDIR_GenFlags] & 2;
  }
#  endif
#endif

  if ((uint)*path < ' ') { /* Null path name is the origin directory itself */
    dp->fn[NSFLAG] = NS_NONAME;
    res            = dir_sdi(dp, 0);

  } else { /* Follow path */
    for (;;) {
      res = create_name(dp, &path); /* Get a segment name of the path */
      if (res != FR_OK) break;
      res = dir_find(dp); /* Find an object with the segment name */
      ns  = dp->fn[NSFLAG];
      if (res != FR_OK) {                     /* Failed to find the object */
        if (res == FR_NO_FILE) {              /* Object is not found */
          if (FF_FS_RPATH && (ns & NS_DOT)) { /* If dot entry is not exist, stay there */
            if (!(ns & NS_LAST)) continue;    /* Continue to follow if not last segment */
            dp->fn[NSFLAG] = NS_NONAME;
            res            = FR_OK;
          } else {                                 /* Could not find the object */
            if (!(ns & NS_LAST)) res = FR_NO_PATH; /* Adjust error code if not last segment */
          }
        }
        break;
      }
      if (ns & NS_LAST) break; /* Last segment matched. Function completed. */
      /* Get into the sub-directory */
      if (!(dp->obj.attr & AM_DIR)) { /* It is not a sub-directory and cannot follow */
        res = FR_NO_PATH;
        break;
      }
#if FF_FS_EXFAT
      if (fs->fs_type == FS_EXFAT) { /* Save containing directory information for next dir */
        dp->obj.c_scl  = dp->obj.sclust;
        dp->obj.c_size = ((u32)dp->obj.objsize & 0xFFFFFF00) | dp->obj.stat;
        dp->obj.c_ofs  = dp->blk_ofs;
        init_alloc_info(fs, &dp->obj); /* Open next directory */
      } else
#endif
      {
        dp->obj.sclust = ld_clust(fs, fs->win + dp->dptr % SS(fs)); /* Open next directory */
      }
    }
  }

  return res;
}

/*-----------------------------------------------------------------------*/
/* Get logical drive number from path name                               */
/*-----------------------------------------------------------------------*/

static int get_ldnumber(/* Returns logical drive number (-1:invalid drive number or null pointer) */
                        const TCHAR **path /* Pointer to pointer to the path name */
) {
  const TCHAR *tp;
  const TCHAR *tt;
  TCHAR        tc;
  int          i;
  int          vol = -1;
#if FF_STR_VOLUME_ID /* Find string volume ID */
  const char *sp;
  char        c;
#endif

  tt = tp = *path;
  if (!tp) return vol; /* Invalid path name? */
  do {                 /* Find a colon in the path */
    tc = *tt++;
  } while (!IsTerminator(tc) && tc != ':');

  if (tc == ':') { /* DOS/Windows style volume ID? */
    i = FF_VOLUMES;
    if (IsDigit(*tp) && tp + 2 == tt) { /* Is there a numeric volume ID + colon? */
      i = (int)*tp - '0';               /* Get the LD number */
    }
#if FF_STR_VOLUME_ID == 1 /* Arbitrary string is enabled */
    else {
      i = 0;
      do {
        sp = VolumeStr[i];
        tp = *path; /* This string volume ID and path name */
        do {        /* Compare the volume ID with path name */
          c  = *sp++;
          tc = *tp++;
          if (IsLower(c)) c -= 0x20;
          if (IsLower(tc)) tc -= 0x20;
        } while (c && (TCHAR)c == tc);
      } while ((c || tp != tt) && ++i < FF_VOLUMES); /* Repeat for each id until pattern match */
    }
#endif
    if (i < FF_VOLUMES) { /* If a volume ID is found, get the drive number and strip it */
      vol   = i;          /* Drive number */
      *path = tt;         /* Snip the drive prefix off */
    }
    return vol;
  }
#if FF_STR_VOLUME_ID == 2 /* Unix style volume ID is enabled */
  if (*tp == '/') {       /* Is there a volume ID? */
    while (*(tp + 1) == '/')
      tp++; /* Skip duplicated separator */
    i = 0;
    do {
      tt = tp;
      sp = VolumeStr[i]; /* Path name and this string volume ID */
      do {               /* Compare the volume ID with path name */
        c  = *sp++;
        tc = *(++tt);
        if (IsLower(c)) c -= 0x20;
        if (IsLower(tc)) tc -= 0x20;
      } while (c && (TCHAR)c == tc);
    } while ((c || (tc != '/' && !IsTerminator(tc))) &&
             ++i < FF_VOLUMES); /* Repeat for each ID until pattern match */
    if (i < FF_VOLUMES) {       /* If a volume ID is found, get the drive number and strip it */
      vol   = i;                /* Drive number */
      *path = tt;               /* Snip the drive prefix off */
    }
    return vol;
  }
#endif
  /* No drive prefix is found */
#if FF_FS_RPATH != 0
  vol = CurrVol; /* Default drive is current drive */
#else
  vol = 0; /* Default drive is 0 */
#endif
  return vol; /* Return the default drive */
}

/*-----------------------------------------------------------------------*/
/* GPT support functions                                                 */
/*-----------------------------------------------------------------------*/

#if FF_LBA64

/* Calculate CRC32 in byte-by-byte */

static u32 crc32(          /* Returns next CRC value */
                 u32  crc, /* Current CRC value */
                 byte d    /* A byte to be processed */
) {
  byte b;

  for (b = 1; b; b <<= 1) {
    crc ^= (d & b) ? 1 : 0;
    crc  = (crc & 1) ? crc >> 1 ^ 0xEDB88320 : crc >> 1;
  }
  return crc;
}

/* Check validity of GPT header */

static int test_gpt_header(                 /* 0:Invalid, 1:Valid */
                           const byte *gpth /* Pointer to the GPT header */
) {
  uint i;
  u32  bcc, hlen;

  if (memcmp(gpth + GPTH_Sign,
             "EFI PART"
             "\0\0\1",
             12))
    return 0;                        /* Check signature and version (1.0) */
  hlen = ld_dword(gpth + GPTH_Size); /* Check header size */
  if (hlen < 92 || hlen > FF_MIN_SS) return 0;
  for (i = 0, bcc = 0xFFFFFFFF; i < hlen; i++) { /* Check header BCC */
    bcc = crc32(bcc, i - GPTH_Bcc < 4 ? 0 : gpth[i]);
  }
  if (~bcc != ld_dword(gpth + GPTH_Bcc)) return 0;
  if (ld_dword(gpth + GPTH_PteSize) != SZ_GPTE)
    return 0;                                      /* Table entry size (must be SZ_GPTE bytes) */
  if (ld_dword(gpth + GPTH_PtNum) > 128) return 0; /* Table size (must be 128 entries or less) */

  return 1;
}

#  if !FF_FS_READONLY && FF_USE_MKFS

/* Generate random value */
static u32 make_rand(u32   seed, /* Seed value */
                     byte *buff, /* Output buffer */
                     uint  n     /* Data length */
) {
  uint r;

  if (seed == 0) seed = 1;
  do {
    for (r = 0; r < 8; r++)
      seed = seed & 1 ? seed >> 1 ^ 0xA3000000 : seed >> 1; /* Shift 8 bits the 32-bit LFSR */
    *buff++ = (byte)seed;
  } while (--n);
  return seed;
}

#  endif
#endif

/*-----------------------------------------------------------------------*/
/* Load a sector and check if it is an FAT VBR                           */
/*-----------------------------------------------------------------------*/

/* Check what the sector is */

static uint
check_fs(/* 0:FAT/FAT32 VBR, 1:exFAT VBR, 2:Not FAT and valid BS, 3:Not FAT and invalid BS, 4:Disk error */
         FATFS *fs,  /* Filesystem object */
         LBA_t  sect /* Sector to load and check if it is an FAT-VBR or not */
) {
  u16  w, sign;
  byte b;

  fs->wflag   = 0;
  fs->winsect = (LBA_t)0 - 1;                   /* Invaidate window */
  if (move_window(fs, sect) != FR_OK) return 4; /* Load the boot sector */
  sign = ld_word(fs->win + BS_55AA);
#if FF_FS_EXFAT
  if (sign == 0xAA55 && !memcmp(fs->win + BS_JmpBoot,
                                "\xEB\x76\x90"
                                "EXFAT   ",
                                11))
    return 1; /* It is an exFAT VBR */
#endif
  b = fs->win[BS_JmpBoot];
  if (b == 0xEB || b == 0xE9 ||
      b == 0xE8) { /* Valid JumpBoot code? (short jump, near jump or near call) */
    if (sign == 0xAA55 && !memcmp(fs->win + BS_FilSysType32, "FAT32   ", 8)) {
      return 0; /* It is an FAT32 VBR */
    }
    /* FAT volumes formatted with early MS-DOS lack BS_55AA and BS_FilSysType, so FAT VBR needs to be identified without them. */
    w = ld_word(fs->win + BPB_BytsPerSec);
    b = fs->win[BPB_SecPerClus];
    if ((w & (w - 1)) == 0 && w >= FF_MIN_SS &&
        w <= FF_MAX_SS                            /* Properness of sector size (512-4096 and 2^n) */
        && b != 0 && (b & (b - 1)) == 0           /* Properness of cluster size (2^n) */
        && ld_word(fs->win + BPB_RsvdSecCnt) != 0 /* Properness of reserved sectors (MNBZ) */
        && (uint)fs->win[BPB_NumFATs] - 1 <= 1    /* Properness of FATs (1 or 2) */
        && ld_word(fs->win + BPB_RootEntCnt) != 0 /* Properness of root dir entries (MNBZ) */
        && (ld_word(fs->win + BPB_TotSec16) >= 128 ||
            ld_dword(fs->win + BPB_TotSec32) >= 0x10000) /* Properness of volume sectors (>=128) */
        && ld_word(fs->win + BPB_FATSz16) != 0) {        /* Properness of FAT size (MNBZ) */
      return 0;                                          /* It can be presumed an FAT VBR */
    }
  }
  return sign == 0xAA55 ? 2 : 3; /* Not an FAT VBR (valid or invalid BS) */
}

/* Find an FAT volume */
/* (It supports only generic partitioning rules, MBR, GPT and SFD) */

static uint
find_volume(           /* Returns BS status found in the hosting drive */
            FATFS *fs, /* Filesystem object */
            uint
                part /* Partition to fined = 0:find as SFD and partitions, >0:forced partition number */
) {
  uint fmt, i;
  u32  mbr_pt[4];

  fmt = check_fs(fs, 0); /* Load sector 0 and check if it is an FAT VBR as SFD format */
  if (fmt != 2 && (fmt >= 3 || part == 0))
    return fmt; /* Returns if it is an FAT VBR as auto scan, not a BS or disk error */

    /* Sector 0 is not an FAT VBR or forced partition number wants a partition */

#if FF_LBA64
  if (fs->win[MBR_Table + PTE_System] == 0xEE) { /* GPT protective MBR? */
    u32 n_ent, v_ent, ofs;
    u64 pt_lba;

    if (move_window(fs, 1) != FR_OK) return 4; /* Load GPT header sector (next to MBR) */
    if (!test_gpt_header(fs->win)) return 3;   /* Check if GPT header is valid */
    n_ent  = ld_dword(fs->win + GPTH_PtNum);   /* Number of entries */
    pt_lba = ld_qword(fs->win + GPTH_PtOfs);   /* Table location */
    for (v_ent = i = 0; i < n_ent; i++) {      /* Find FAT partition */
      if (move_window(fs, pt_lba + i * SZ_GPTE / SS(fs)) != FR_OK) return 4; /* PT sector */
      ofs = i * SZ_GPTE % SS(fs);                                    /* Offset in the sector */
      if (!memcmp(fs->win + ofs + GPTE_PtGuid, GUID_MS_Basic, 16)) { /* MS basic data partition? */
        v_ent++;
        fmt = check_fs(fs, ld_qword(fs->win + ofs + GPTE_FstLba)); /* Load VBR and check status */
        if (part == 0 && fmt <= 1) return fmt; /* Auto search (valid FAT volume found first) */
        if (part != 0 && v_ent == part)
          return fmt; /* Forced partition order (regardless of it is valid or not) */
      }
    }
    return 3; /* Not found */
  }
#endif
  if (FF_MULTI_PARTITION && part > 4) return 3; /* MBR has 4 partitions max */
  for (i = 0; i < 4; i++) {                     /* Load partition offset in the MBR */
    mbr_pt[i] = ld_dword(fs->win + MBR_Table + i * SZ_PTE + PTE_StLba);
  }
  i = part ? part - 1 : 0;                         /* Table index to find first */
  do {                                             /* Find an FAT volume */
    fmt = mbr_pt[i] ? check_fs(fs, mbr_pt[i]) : 3; /* Check if the partition is FAT */
  } while (part == 0 && fmt >= 2 && ++i < 4);
  return fmt;
}

/*-----------------------------------------------------------------------*/
/* Determine logical drive number and mount the volume if needed         */
/*-----------------------------------------------------------------------*/

static FRESULT
mount_volume(                    /* FR_OK(0): successful, !=0: an error occurred */
             const TCHAR **path, /* Pointer to pointer to the path name (drive number) */
             FATFS       **rfs,  /* Pointer to pointer to the found filesystem object */
             byte          mode  /* Desiered access mode to check write protection */
) {
  int     vol;
  FATFS  *fs;
  DSTATUS stat;
  LBA_t   bsect;
  u32     tsect, sysect, fasize, nclst, szbfat;
  u16     nrsv;
  uint    fmt;

  /* Get logical drive number */
  *rfs = 0;
  vol  = get_ldnumber(path);
  if (vol < 0) return FR_INVALID_DRIVE;

  /* Check if the filesystem object is valid or not */
  fs = FatFs[vol];                /* Get pointer to the filesystem object */
  if (!fs) return FR_NOT_ENABLED; /* Is the filesystem object available? */
#if FF_FS_REENTRANT
  if (!lock_volume(fs, 1)) return FR_TIMEOUT; /* Lock the volume, and system if needed */
#endif
  *rfs = fs; /* Return pointer to the filesystem object */

  mode &= (byte)~FA_READ; /* Desired access mode, write access or not */
  if (fs->fs_type != 0) { /* If the volume has been mounted */
    stat = disk_status(fs->pdrv);
    if (!(stat & STA_NOINIT)) { /* and the physical drive is kept initialized */
      if (!FF_FS_READONLY && mode && (stat & STA_PROTECT)) { /* Check write protection if needed */
        return FR_WRITE_PROTECTED;
      }
      return FR_OK; /* The filesystem object is already valid */
    }
  }

  /* The filesystem object is not valid. */
  /* Following code attempts to mount the volume. (find an FAT volume, analyze the BPB and initialize the filesystem object) */

  fs->fs_type = 0;                         /* Invalidate the filesystem object */
  stat        = disk_initialize(fs->pdrv); /* Initialize the volume hosting physical drive */
  if (stat & STA_NOINIT) {                 /* Check if the initialization succeeded */
    return FR_NOT_READY;                   /* Failed to initialize due to no medium or hard error */
  }
  if (!FF_FS_READONLY && mode && (stat & STA_PROTECT)) { /* Check disk write protection if needed */
    return FR_WRITE_PROTECTED;
  }
#if FF_MAX_SS != FF_MIN_SS /* Get sector size (multiple sector size cfg only) */
  if (disk_ioctl(fs->pdrv, GET_SECTOR_SIZE, &SS(fs)) != RES_OK) return FR_DISK_ERR;
  if (SS(fs) > FF_MAX_SS || SS(fs) < FF_MIN_SS || (SS(fs) & (SS(fs) - 1))) return FR_DISK_ERR;
#endif

  /* Find an FAT volume on the hosting drive */
  fmt = find_volume(fs, LD2PT(vol));
  if (fmt == 4) return FR_DISK_ERR;      /* An error occurred in the disk I/O layer */
  if (fmt >= 2) return FR_NO_FILESYSTEM; /* No FAT volume is found */
  bsect = fs->winsect;                   /* Volume offset in the hosting physical drive */

  /* An FAT volume is found (bsect). Following code initializes the filesystem object */

#if FF_FS_EXFAT
  if (fmt == 1) {
    u64 maxlba;
    u32 so, cv, bcl, i;

    for (i = BPB_ZeroedEx; i < BPB_ZeroedEx + 53 && fs->win[i] == 0; i++)
      ; /* Check zero filler */
    if (i < BPB_ZeroedEx + 53) return FR_NO_FILESYSTEM;

    if (ld_word(fs->win + BPB_FSVerEx) != 0x100)
      return FR_NO_FILESYSTEM; /* Check exFAT version (must be version 1.0) */

    if (1 << fs->win[BPB_BytsPerSecEx] !=
        SS(fs)) { /* (BPB_BytsPerSecEx must be equal to the physical sector size) */
      return FR_NO_FILESYSTEM;
    }

    maxlba = ld_qword(fs->win + BPB_TotSecEx) + bsect; /* Last LBA of the volume + 1 */
    if (!FF_LBA64 && maxlba >= 0x100000000)
      return FR_NO_FILESYSTEM; /* (It cannot be accessed in 32-bit LBA) */

    fs->fsize = ld_dword(fs->win + BPB_FatSzEx); /* Number of sectors per FAT */

    fs->n_fats = fs->win[BPB_NumFATsEx];          /* Number of FATs */
    if (fs->n_fats != 1) return FR_NO_FILESYSTEM; /* (Supports only 1 FAT) */

    fs->csize = 1 << fs->win[BPB_SecPerClusEx];  /* Cluster size */
    if (fs->csize == 0) return FR_NO_FILESYSTEM; /* (Must be 1..32768 sectors) */

    nclst = ld_dword(fs->win + BPB_NumClusEx);      /* Number of clusters */
    if (nclst > MAX_EXFAT) return FR_NO_FILESYSTEM; /* (Too many clusters) */
    fs->n_fatent = nclst + 2;

    /* Boundaries and Limits */
    fs->volbase  = bsect;
    fs->database = bsect + ld_dword(fs->win + BPB_DataOfsEx);
    fs->fatbase  = bsect + ld_dword(fs->win + BPB_FatOfsEx);
    if (maxlba < (u64)fs->database + nclst * fs->csize)
      return FR_NO_FILESYSTEM; /* (Volume size must not be smaller than the size required) */
    fs->dirbase = ld_dword(fs->win + BPB_RootClusEx);

    /* Get bitmap location and check if it is contiguous (implementation assumption) */
    so = i = 0;
    for (;;) { /* Find the bitmap entry in the root directory (in only first cluster) */
      if (i == 0) {
        if (so >= fs->csize) return FR_NO_FILESYSTEM; /* Not found? */
        if (move_window(fs, clst2sect(fs, (u32)fs->dirbase) + so) != FR_OK) return FR_DISK_ERR;
        so++;
      }
      if (fs->win[i] == ET_BITMAP) break; /* Is it a bitmap entry? */
      i = (i + SZDIRE) % SS(fs);          /* Next entry */
    }
    bcl = ld_dword(fs->win + i + 20);                            /* Bitmap cluster */
    if (bcl < 2 || bcl >= fs->n_fatent) return FR_NO_FILESYSTEM; /* (Wrong cluster#) */
    fs->bitbase = fs->database + fs->csize * (bcl - 2);          /* Bitmap sector */
    for (;;) {                                                   /* Check if bitmap is contiguous */
      if (move_window(fs, fs->fatbase + bcl / (SS(fs) / 4)) != FR_OK) return FR_DISK_ERR;
      cv = ld_dword(fs->win + bcl % (SS(fs) / 4) * 4);
      if (cv == 0xFFFFFFFF) break;              /* Last link? */
      if (cv != ++bcl) return FR_NO_FILESYSTEM; /* Fragmented bitmap? */
    }

#  if !FF_FS_READONLY
    fs->last_clst = fs->free_clst = 0xFFFFFFFF; /* Initialize cluster allocation information */
#  endif
    fmt = FS_EXFAT; /* FAT sub-type */
  } else
#endif /* FF_FS_EXFAT */
  {
    if (ld_word(fs->win + BPB_BytsPerSec) != SS(fs))
      return FR_NO_FILESYSTEM; /* (BPB_BytsPerSec must be equal to the physical sector size) */

    fasize = ld_word(fs->win + BPB_FATSz16); /* Number of sectors per FAT */
    if (fasize == 0) fasize = ld_dword(fs->win + BPB_FATSz32);
    fs->fsize = fasize;

    fs->n_fats = fs->win[BPB_NumFATs];                               /* Number of FATs */
    if (fs->n_fats != 1 && fs->n_fats != 2) return FR_NO_FILESYSTEM; /* (Must be 1 or 2) */
    fasize *= fs->n_fats; /* Number of sectors for FAT area */

    fs->csize = fs->win[BPB_SecPerClus]; /* Cluster size */
    if (fs->csize == 0 || (fs->csize & (fs->csize - 1)))
      return FR_NO_FILESYSTEM; /* (Must be power of 2) */

    fs->n_rootdir = ld_word(fs->win + BPB_RootEntCnt); /* Number of root directory entries */
    if (fs->n_rootdir % (SS(fs) / SZDIRE)) return FR_NO_FILESYSTEM; /* (Must be sector aligned) */

    tsect = ld_word(fs->win + BPB_TotSec16); /* Number of sectors on the volume */
    if (tsect == 0) tsect = ld_dword(fs->win + BPB_TotSec32);

    nrsv = ld_word(fs->win + BPB_RsvdSecCnt); /* Number of reserved sectors */
    if (nrsv == 0) return FR_NO_FILESYSTEM;   /* (Must not be 0) */

    /* Determine the FAT sub type */
    sysect = nrsv + fasize + fs->n_rootdir / (SS(fs) / SZDIRE); /* RSV + FAT + DIR */
    if (tsect < sysect) return FR_NO_FILESYSTEM;                /* (Invalid volume size) */
    nclst = (tsect - sysect) / fs->csize;                       /* Number of clusters */
    if (nclst == 0) return FR_NO_FILESYSTEM;                    /* (Invalid volume size) */
    fmt = 0;
    if (nclst <= MAX_FAT32) fmt = FS_FAT32;
    if (nclst <= MAX_FAT16) fmt = FS_FAT16;
    if (nclst <= MAX_FAT12) fmt = FS_FAT12;
    if (fmt == 0) return FR_NO_FILESYSTEM;

    /* Boundaries and Limits */
    fs->n_fatent = nclst + 2;      /* Number of FAT entries */
    fs->volbase  = bsect;          /* Volume start sector */
    fs->fatbase  = bsect + nrsv;   /* FAT start sector */
    fs->database = bsect + sysect; /* Data start sector */
    if (fmt == FS_FAT32) {
      if (ld_word(fs->win + BPB_FSVer32) != 0)
        return FR_NO_FILESYSTEM;                        /* (Must be FAT32 revision 0.0) */
      if (fs->n_rootdir != 0) return FR_NO_FILESYSTEM;  /* (BPB_RootEntCnt must be 0) */
      fs->dirbase = ld_dword(fs->win + BPB_RootClus32); /* Root directory start cluster */
      szbfat      = fs->n_fatent * 4;                   /* (Needed FAT size) */
    } else {
      if (fs->n_rootdir == 0) return FR_NO_FILESYSTEM; /* (BPB_RootEntCnt must not be 0) */
      fs->dirbase = fs->fatbase + fasize;              /* Root directory start sector */
      szbfat      = (fmt == FS_FAT16) ?                /* (Needed FAT size) */
                   fs->n_fatent * 2
                                      : fs->n_fatent * 3 / 2 + (fs->n_fatent & 1);
    }
    if (fs->fsize < (szbfat + (SS(fs) - 1)) / SS(fs))
      return FR_NO_FILESYSTEM; /* (BPB_FATSz must not be less than the size needed) */

#if !FF_FS_READONLY
    /* Get FSInfo if available */
    fs->last_clst = fs->free_clst = 0xFFFFFFFF; /* Initialize cluster allocation information */
    fs->fsi_flag                  = 0x80;
#  if (FF_FS_NOFSINFO & 3) != 3
    if (fmt == FS_FAT32 /* Allow to update FSInfo only if BPB_FSInfo32 == 1 */
        && ld_word(fs->win + BPB_FSInfo32) == 1 && move_window(fs, bsect + 1) == FR_OK) {
      fs->fsi_flag = 0;
      if (ld_word(fs->win + BS_55AA) == 0xAA55 /* Load FSInfo data if available */
          && ld_dword(fs->win + FSI_LeadSig) == 0x41615252 &&
          ld_dword(fs->win + FSI_StrucSig) == 0x61417272) {
#    if (FF_FS_NOFSINFO & 1) == 0
        fs->free_clst = ld_dword(fs->win + FSI_Free_Count);
#    endif
#    if (FF_FS_NOFSINFO & 2) == 0
        fs->last_clst = ld_dword(fs->win + FSI_Nxt_Free);
#    endif
      }
    }
#  endif /* (FF_FS_NOFSINFO & 3) != 3 */
#endif   /* !FF_FS_READONLY */
  }

  fs->fs_type = (byte)fmt; /* FAT sub-type (the filesystem object gets valid) */
  fs->id      = ++Fsid;    /* Volume mount ID */
#if FF_USE_LFN == 1
  fs->lfnbuf = LfnBuf; /* Static LFN working buffer */
#  if FF_FS_EXFAT
  fs->dirbuf = DirBuf; /* Static directory block scratchpad buuffer */
#  endif
#endif
#if FF_FS_RPATH != 0
  fs->cdir = 0; /* Initialize current directory */
#endif
#if FF_FS_LOCK /* Clear file lock semaphores */
  clear_share(fs);
#endif
  return FR_OK;
}

/*-----------------------------------------------------------------------*/
/* Check if the file/directory object is valid or not                    */
/*-----------------------------------------------------------------------*/

static FRESULT
validate(/* Returns FR_OK or FR_INVALID_OBJECT */
         FFOBJID *
             obj, /* Pointer to the FFOBJID, the 1st member in the FIL/DIR structure, to check validity */
         FATFS **rfs /* Pointer to pointer to the owner filesystem object to return */
) {
  FRESULT res = FR_INVALID_OBJECT;

  if (obj && obj->fs && obj->fs->fs_type &&
      obj->id == obj->fs->id) { /* Test if the object is valid */
#if FF_FS_REENTRANT
    if (lock_volume(obj->fs, 0)) { /* Take a grant to access the volume */
      if (!(disk_status(obj->fs->pdrv) &
            STA_NOINIT)) { /* Test if the hosting phsical drive is kept initialized */
        res = FR_OK;
      } else {
        unlock_volume(obj->fs, FR_OK); /* Invalidated volume, abort to access */
      }
    } else { /* Could not take */
      res = FR_TIMEOUT;
    }
#else
    if (!(disk_status(obj->fs->pdrv) &
          STA_NOINIT)) { /* Test if the hosting phsical drive is kept initialized */
      res = FR_OK;
    }
#endif
  }
  *rfs = (res == FR_OK) ? obj->fs : 0; /* Return corresponding filesystem object if it is valid */
  return res;
}

/*---------------------------------------------------------------------------

   Public Functions (FatFs API)

----------------------------------------------------------------------------*/

/*-----------------------------------------------------------------------*/
/* Mount/Unmount a Logical Drive                                         */
/*-----------------------------------------------------------------------*/

FRESULT f_mount(FATFS *fs, /* Pointer to the filesystem object to be registered (NULL:unmount)*/
                const TCHAR *path, /* Logical drive number to be mounted/unmounted */
                byte opt /* Mount option: 0=Do not mount (delayed mount), 1=Mount immediately */
) {
  FATFS       *cfs;
  int          vol;
  FRESULT      res;
  const TCHAR *rp = path;

  /* Get volume ID (logical drive number) */
  vol = get_ldnumber(&rp);
  if (vol < 0) return FR_INVALID_DRIVE;
  cfs = FatFs[vol]; /* Pointer to the filesystem object of the volume */

  if (cfs) { /* Unregister current filesystem object if regsitered */
    FatFs[vol] = 0;
#if FF_FS_LOCK
    clear_share(cfs);
#endif
#if FF_FS_REENTRANT /* Discard mutex of the current volume */
    ff_mutex_delete(vol);
#endif
    cfs->fs_type = 0; /* Invalidate the filesystem object to be unregistered */
  }

  if (fs) {                /* Register new filesystem object */
    fs->pdrv = LD2PD(vol); /* Volume hosting physical drive */
#if FF_FS_REENTRANT        /* Create a volume mutex */
    fs->ldrv = (byte)vol;  /* Owner volume ID */
    if (!ff_mutex_create(vol)) return FR_INT_ERR;
#  if FF_FS_LOCK
    if (SysLock == 0) { /* Create a system mutex if needed */
      if (!ff_mutex_create(FF_VOLUMES)) {
        ff_mutex_delete(vol);
        return FR_INT_ERR;
      }
      SysLock = 1; /* System mutex is ready */
    }
#  endif
#endif
    fs->fs_type = 0;  /* Invalidate the new filesystem object */
    FatFs[vol]  = fs; /* Register new fs object */
  }

  if (opt == 0)
    return FR_OK; /* Do not mount now, it will be mounted in subsequent file functions */

  res = mount_volume(&path, &fs, 0); /* Force mounted the volume */
  LEAVE_FF(fs, res);
}

/*-----------------------------------------------------------------------*/
/* Open or Create a File                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_open(FIL         *fp,   /* Pointer to the blank file object */
               const TCHAR *path, /* Pointer to the file name */
               byte         mode  /* Access mode and open mode flags */
) {
  FRESULT res;
  DIR     dj;
  FATFS  *fs;
#if !FF_FS_READONLY
  u32     cl, bcs, clst, tm;
  LBA_t   sc;
  FSIZE_t ofs;
#endif
  DEF_NAMBUF

  if (!fp) return FR_INVALID_OBJECT;

  /* Get logical drive number */
  mode &= FF_FS_READONLY ? FA_READ
                         : FA_READ | FA_WRITE | FA_CREATE_ALWAYS | FA_CREATE_NEW | FA_OPEN_ALWAYS |
                               FA_OPEN_APPEND;
  res   = mount_volume(&path, &fs, mode);
  if (res == FR_OK) {
    dj.obj.fs = fs;
    INIT_NAMBUF(fs);
    res = follow_path(&dj, path); /* Follow the file path */
#if !FF_FS_READONLY               /* Read/Write configuration */
    if (res == FR_OK) {
      if (dj.fn[NSFLAG] & NS_NONAME) { /* Origin directory itself? */
        res = FR_INVALID_NAME;
      }
#  if FF_FS_LOCK
      else {
        res = chk_share(&dj, (mode & ~FA_READ) ? 1 : 0); /* Check if the file can be used */
      }
#  endif
    }
    /* Create or Open a file */
    if (mode & (FA_CREATE_ALWAYS | FA_OPEN_ALWAYS | FA_CREATE_NEW)) {
      if (res != FR_OK) {        /* No file, create new */
        if (res == FR_NO_FILE) { /* There is no file to open, create a new entry */
#  if FF_FS_LOCK
          res = enq_share() ? dir_register(&dj) : FR_TOO_MANY_OPEN_FILES;
#  else
          res = dir_register(&dj);
#  endif
        }
        mode |= FA_CREATE_ALWAYS; /* File is created */
      } else {                    /* Any object with the same name is already existing */
        if (dj.obj.attr & (AM_RDO | AM_DIR)) { /* Cannot overwrite it (R/O or DIR) */
          res = FR_DENIED;
        } else {
          if (mode & FA_CREATE_NEW) res = FR_EXIST; /* Cannot create as new file */
        }
      }
      if (res == FR_OK && (mode & FA_CREATE_ALWAYS)) { /* Truncate the file if overwrite mode */
#  if FF_FS_EXFAT
        if (fs->fs_type == FS_EXFAT) {
          /* Get current allocation info */
          fp->obj.fs = fs;
          init_alloc_info(fs, &fp->obj);
          /* Set directory entry block initial state */
          memset(fs->dirbuf + 2, 0, 30);  /* Clear 85 entry except for NumSec */
          memset(fs->dirbuf + 38, 0, 26); /* Clear C0 entry except for NumName and NameHash */
          fs->dirbuf[XDIR_Attr] = AM_ARC;
          st_dword(fs->dirbuf + XDIR_CrtTime, GET_FATTIME());
          fs->dirbuf[XDIR_GenFlags] = 1;
          res                       = store_xdir(&dj);
          if (res == FR_OK && fp->obj.sclust != 0) { /* Remove the cluster chain if exist */
            res           = remove_chain(&fp->obj, fp->obj.sclust, 0);
            fs->last_clst = fp->obj.sclust - 1; /* Reuse the cluster hole */
          }
        } else
#  endif
        {
          /* Set directory entry initial state */
          tm = GET_FATTIME(); /* Set created time */
          st_dword(dj.dir + DIR_CrtTime, tm);
          st_dword(dj.dir + DIR_ModTime, tm);
          cl               = ld_clust(fs, dj.dir); /* Get current cluster chain */
          dj.dir[DIR_Attr] = AM_ARC;               /* Reset attribute */
          st_clust(fs, dj.dir, 0);                 /* Reset file allocation info */
          st_dword(dj.dir + DIR_FileSize, 0);
          fs->wflag = 1;
          if (cl != 0) { /* Remove the cluster chain if exist */
            sc  = fs->winsect;
            res = remove_chain(&dj.obj, cl, 0);
            if (res == FR_OK) {
              res           = move_window(fs, sc);
              fs->last_clst = cl - 1; /* Reuse the cluster hole */
            }
          }
        }
      }
    } else {                        /* Open an existing file */
      if (res == FR_OK) {           /* Is the object exsiting? */
        if (dj.obj.attr & AM_DIR) { /* File open against a directory */
          res = FR_NO_FILE;
        } else {
          if ((mode & FA_WRITE) && (dj.obj.attr & AM_RDO)) { /* Write mode open against R/O file */
            res = FR_DENIED;
          }
        }
      }
    }
    if (res == FR_OK) {
      if (mode & FA_CREATE_ALWAYS)
        mode |= FA_MODIFIED;      /* Set file change flag if created or overwritten */
      fp->dir_sect = fs->winsect; /* Pointer to the directory entry */
      fp->dir_ptr  = dj.dir;
#  if FF_FS_LOCK
      fp->obj.lockid =
          inc_share(&dj, (mode & ~FA_READ) ? 1 : 0); /* Lock the file for this session */
      if (fp->obj.lockid == 0) res = FR_INT_ERR;
#  endif
    }
#else /* R/O configuration */
    if (res == FR_OK) {
      if (dj.fn[NSFLAG] & NS_NONAME) { /* Is it origin directory itself? */
        res = FR_INVALID_NAME;
      } else {
        if (dj.obj.attr & AM_DIR) { /* Is it a directory? */
          res = FR_NO_FILE;
        }
      }
    }
#endif

    if (res == FR_OK) {
#if FF_FS_EXFAT
      if (fs->fs_type == FS_EXFAT) {
        fp->obj.c_scl  = dj.obj.sclust; /* Get containing directory info */
        fp->obj.c_size = ((u32)dj.obj.objsize & 0xFFFFFF00) | dj.obj.stat;
        fp->obj.c_ofs  = dj.blk_ofs;
        init_alloc_info(fs, &fp->obj);
      } else
#endif
      {
        fp->obj.sclust  = ld_clust(fs, dj.dir); /* Get object allocation info */
        fp->obj.objsize = ld_dword(dj.dir + DIR_FileSize);
      }
#if FF_USE_FASTSEEK
      fp->cltbl = 0; /* Disable fast seek mode */
#endif
      fp->obj.fs = fs; /* Validate the file object */
      fp->obj.id = fs->id;
      fp->flag   = mode; /* Set file access mode */
      fp->err    = 0;    /* Clear error flag */
      fp->sect   = 0;    /* Invalidate current data sector */
      fp->fptr   = 0;    /* Set file pointer top of the file */
#if !FF_FS_READONLY
#  if !FF_FS_TINY
      memset(fp->buf, 0, sizeof fp->buf); /* Clear sector buffer */
#  endif
      if ((mode & FA_SEEKEND) &&
          fp->obj.objsize > 0) {            /* Seek to end of file if FA_OPEN_APPEND is specified */
        fp->fptr = fp->obj.objsize;         /* Offset to seek */
        bcs      = (u32)fs->csize * SS(fs); /* Cluster size in byte */
        clst     = fp->obj.sclust;          /* Follow the cluster chain */
        for (ofs = fp->obj.objsize; res == FR_OK && ofs > bcs; ofs -= bcs) {
          clst = get_fat(&fp->obj, clst);
          if (clst <= 1) res = FR_INT_ERR;
          if (clst == 0xFFFFFFFF) res = FR_DISK_ERR;
        }
        fp->clust = clst;
        if (res == FR_OK && ofs % SS(fs)) { /* Fill sector buffer if not on the sector boundary */
          sc = clst2sect(fs, clst);
          if (sc == 0) {
            res = FR_INT_ERR;
          } else {
            fp->sect = sc + (u32)(ofs / SS(fs));
#  if !FF_FS_TINY
            if (disk_read(fs->pdrv, fp->buf, fp->sect, 1) != RES_OK) res = FR_DISK_ERR;
#  endif
          }
        }
#  if FF_FS_LOCK
        if (res != FR_OK)
          dec_share(fp->obj.lockid); /* Decrement file open counter if seek failed */
#  endif
      }
#endif
    }

    FREE_NAMBUF();
  }

  if (res != FR_OK) fp->obj.fs = 0; /* Invalidate file object on error */

  LEAVE_FF(fs, res);
}

/*-----------------------------------------------------------------------*/
/* Read File                                                             */
/*-----------------------------------------------------------------------*/

FRESULT f_read(FIL  *fp,   /* Open file to be read */
               void *buff, /* Data buffer to store the read data */
               uint  btr,  /* Number of bytes to read */
               uint *br    /* Number of bytes read */
) {
  FRESULT res;
  FATFS  *fs;
  u32     clst;
  LBA_t   sect;
  FSIZE_t remain;
  uint    rcnt, cc, csect;
  byte   *rbuff = (byte *)buff;

  *br = 0;                       /* Clear read byte counter */
  res = validate(&fp->obj, &fs); /* Check validity of the file object */
  if (res != FR_OK || (res = (FRESULT)fp->err) != FR_OK) LEAVE_FF(fs, res); /* Check validity */
  if (!(fp->flag & FA_READ)) LEAVE_FF(fs, FR_DENIED);                       /* Check access mode */
  remain = fp->obj.objsize - fp->fptr;
  if (btr > remain) btr = (uint)remain; /* Truncate btr by remaining bytes */

  for (; btr > 0; btr -= rcnt, *br += rcnt, rbuff += rcnt,
                  fp->fptr += rcnt) {                      /* Repeat until btr bytes read */
    if (fp->fptr % SS(fs) == 0) {                          /* On the sector boundary? */
      csect = (uint)(fp->fptr / SS(fs) & (fs->csize - 1)); /* Sector offset in the cluster */
      if (csect == 0) {                                    /* On the cluster boundary? */
        if (fp->fptr == 0) {                               /* On the top of the file? */
          clst = fp->obj.sclust; /* Follow cluster chain from the origin */
        } else {                 /* Middle or end of the file */
#if FF_USE_FASTSEEK
          if (fp->cltbl) {
            clst = clmt_clust(fp, fp->fptr); /* Get cluster# from the CLMT */
          } else
#endif
          {
            clst = get_fat(&fp->obj, fp->clust); /* Follow cluster chain on the FAT */
          }
        }
        if (clst < 2) ABORT(fs, FR_INT_ERR);
        if (clst == 0xFFFFFFFF) ABORT(fs, FR_DISK_ERR);
        fp->clust = clst; /* Update current cluster */
      }
      sect = clst2sect(fs, fp->clust); /* Get current sector */
      if (sect == 0) ABORT(fs, FR_INT_ERR);
      sect += csect;
      cc    = btr / SS(fs);           /* When remaining bytes >= sector size, */
      if (cc > 0) {                   /* Read maximum contiguous sectors directly */
        if (csect + cc > fs->csize) { /* Clip at cluster boundary */
          cc = fs->csize - csect;
        }
        if (disk_read(fs->pdrv, rbuff, sect, cc) != RES_OK) ABORT(fs, FR_DISK_ERR);
#if !FF_FS_READONLY &&                                                                             \
    FF_FS_MINIMIZE <=                                                                              \
        2 /* Replace one of the read sectors with cached data if it contains a dirty sector */
#  if FF_FS_TINY
        if (fs->wflag && fs->winsect - sect < cc) {
          memcpy(rbuff + ((fs->winsect - sect) * SS(fs)), fs->win, SS(fs));
        }
#  else
        if ((fp->flag & FA_DIRTY) && fp->sect - sect < cc) {
          memcpy(rbuff + ((fp->sect - sect) * SS(fs)), fp->buf, SS(fs));
        }
#  endif
#endif
        rcnt = SS(fs) * cc; /* Number of bytes transferred */
        continue;
      }
#if !FF_FS_TINY
      if (fp->sect != sect) { /* Load data sector if not in cache */
#  if !FF_FS_READONLY
        if (fp->flag & FA_DIRTY) { /* Write-back dirty sector cache */
          if (disk_write(fs->pdrv, fp->buf, fp->sect, 1) != RES_OK) ABORT(fs, FR_DISK_ERR);
          fp->flag &= (byte)~FA_DIRTY;
        }
#  endif
        if (disk_read(fs->pdrv, fp->buf, sect, 1) != RES_OK)
          ABORT(fs, FR_DISK_ERR); /* Fill sector cache */
      }
#endif
      fp->sect = sect;
    }
    rcnt = SS(fs) - (uint)fp->fptr % SS(fs); /* Number of bytes remains in the sector */
    if (rcnt > btr) rcnt = btr;              /* Clip it by btr if needed */
#if FF_FS_TINY
    if (move_window(fs, fp->sect) != FR_OK) ABORT(fs, FR_DISK_ERR); /* Move sector window */
    memcpy(rbuff, fs->win + fp->fptr % SS(fs), rcnt);               /* Extract partial sector */
#else
    memcpy(rbuff, fp->buf + fp->fptr % SS(fs), rcnt); /* Extract partial sector */
#endif
  }

  LEAVE_FF(fs, FR_OK);
}

#if !FF_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Write File                                                            */
/*-----------------------------------------------------------------------*/

FRESULT f_write(FIL        *fp,   /* Open file to be written */
                const void *buff, /* Data to be written */
                uint        btw,  /* Number of bytes to write */
                uint       *bw    /* Number of bytes written */
) {
  FRESULT     res;
  FATFS      *fs;
  u32         clst;
  LBA_t       sect;
  uint        wcnt, cc, csect;
  const byte *wbuff = (const byte *)buff;

  *bw = 0;                       /* Clear write byte counter */
  res = validate(&fp->obj, &fs); /* Check validity of the file object */
  if (res != FR_OK || (res = (FRESULT)fp->err) != FR_OK) LEAVE_FF(fs, res); /* Check validity */
  if (!(fp->flag & FA_WRITE)) LEAVE_FF(fs, FR_DENIED);                      /* Check access mode */

  /* Check fptr wrap-around (file size cannot reach 4 GiB at FAT volume) */
  if ((!FF_FS_EXFAT || fs->fs_type != FS_EXFAT) && (u32)(fp->fptr + btw) < (u32)fp->fptr) {
    btw = (uint)(0xFFFFFFFF - (u32)fp->fptr);
  }

  for (; btw > 0; btw -= wcnt, *bw += wcnt, wbuff += wcnt, fp->fptr += wcnt,
                  fp->obj.objsize = (fp->fptr > fp->obj.objsize)
                                        ? fp->fptr
                                        : fp->obj.objsize) { /* Repeat until all data written */
    if (fp->fptr % SS(fs) == 0) {                            /* On the sector boundary? */
      csect = (uint)(fp->fptr / SS(fs)) & (fs->csize - 1);   /* Sector offset in the cluster */
      if (csect == 0) {                                      /* On the cluster boundary? */
        if (fp->fptr == 0) {                                 /* On the top of the file? */
          clst = fp->obj.sclust;                             /* Follow from the origin */
          if (clst == 0) {                                   /* If no cluster is allocated, */
            clst = create_chain(&fp->obj, 0);                /* create a new cluster chain */
          }
        } else { /* On the middle or end of the file */
#  if FF_USE_FASTSEEK
          if (fp->cltbl) {
            clst = clmt_clust(fp, fp->fptr); /* Get cluster# from the CLMT */
          } else
#  endif
          {
            clst =
                create_chain(&fp->obj, fp->clust); /* Follow or stretch cluster chain on the FAT */
          }
        }
        if (clst == 0) break; /* Could not allocate a new cluster (disk full) */
        if (clst == 1) ABORT(fs, FR_INT_ERR);
        if (clst == 0xFFFFFFFF) ABORT(fs, FR_DISK_ERR);
        fp->clust = clst;                               /* Update current cluster */
        if (fp->obj.sclust == 0) fp->obj.sclust = clst; /* Set start cluster if the first write */
      }
#  if FF_FS_TINY
      if (fs->winsect == fp->sect && sync_window(fs) != FR_OK)
        ABORT(fs, FR_DISK_ERR); /* Write-back sector cache */
#  else
      if (fp->flag & FA_DIRTY) { /* Write-back sector cache */
        if (disk_write(fs->pdrv, fp->buf, fp->sect, 1) != RES_OK) ABORT(fs, FR_DISK_ERR);
        fp->flag &= (byte)~FA_DIRTY;
      }
#  endif
      sect = clst2sect(fs, fp->clust); /* Get current sector */
      if (sect == 0) ABORT(fs, FR_INT_ERR);
      sect += csect;
      cc    = btw / SS(fs);           /* When remaining bytes >= sector size, */
      if (cc > 0) {                   /* Write maximum contiguous sectors directly */
        if (csect + cc > fs->csize) { /* Clip at cluster boundary */
          cc = fs->csize - csect;
        }
        if (disk_write(fs->pdrv, wbuff, sect, cc) != RES_OK) ABORT(fs, FR_DISK_ERR);
#  if FF_FS_MINIMIZE <= 2
#    if FF_FS_TINY
        if (fs->winsect - sect <
            cc) { /* Refill sector cache if it gets invalidated by the direct write */
          memcpy(fs->win, wbuff + ((fs->winsect - sect) * SS(fs)), SS(fs));
          fs->wflag = 0;
        }
#    else
        if (fp->sect - sect <
            cc) { /* Refill sector cache if it gets invalidated by the direct write */
          memcpy(fp->buf, wbuff + ((fp->sect - sect) * SS(fs)), SS(fs));
          fp->flag &= (byte)~FA_DIRTY;
        }
#    endif
#  endif
        wcnt = SS(fs) * cc; /* Number of bytes transferred */
        continue;
      }
#  if FF_FS_TINY
      if (fp->fptr >= fp->obj.objsize) { /* Avoid silly cache filling on the growing edge */
        if (sync_window(fs) != FR_OK) ABORT(fs, FR_DISK_ERR);
        fs->winsect = sect;
      }
#  else
      if (fp->sect != sect && /* Fill sector cache with file data */
          fp->fptr < fp->obj.objsize && disk_read(fs->pdrv, fp->buf, sect, 1) != RES_OK) {
        ABORT(fs, FR_DISK_ERR);
      }
#  endif
      fp->sect = sect;
    }
    wcnt = SS(fs) - (uint)fp->fptr % SS(fs); /* Number of bytes remains in the sector */
    if (wcnt > btw) wcnt = btw;              /* Clip it by btw if needed */
#  if FF_FS_TINY
    if (move_window(fs, fp->sect) != FR_OK) ABORT(fs, FR_DISK_ERR); /* Move sector window */
    memcpy(fs->win + fp->fptr % SS(fs), wbuff, wcnt);               /* Fit data to the sector */
    fs->wflag = 1;
#  else
    memcpy(fp->buf + fp->fptr % SS(fs), wbuff, wcnt); /* Fit data to the sector */
    fp->flag |= FA_DIRTY;
#  endif
  }

  fp->flag |= FA_MODIFIED; /* Set file change flag */

  LEAVE_FF(fs, FR_OK);
}

/*-----------------------------------------------------------------------*/
/* Synchronize the File                                                  */
/*-----------------------------------------------------------------------*/

FRESULT f_sync(FIL *fp /* Open file to be synced */
) {
  FRESULT res;
  FATFS  *fs;
  u32     tm;
  byte   *dir;

  res = validate(&fp->obj, &fs); /* Check validity of the file object */
  if (res == FR_OK) {
    if (fp->flag & FA_MODIFIED) { /* Is there any change to the file? */
#  if !FF_FS_TINY
      if (fp->flag & FA_DIRTY) { /* Write-back cached data if needed */
        if (disk_write(fs->pdrv, fp->buf, fp->sect, 1) != RES_OK) LEAVE_FF(fs, FR_DISK_ERR);
        fp->flag &= (byte)~FA_DIRTY;
      }
#  endif
      /* Update the directory entry */
      tm = GET_FATTIME(); /* Modified time */
#  if FF_FS_EXFAT
      if (fs->fs_type == FS_EXFAT) {
        res = fill_first_frag(&fp->obj); /* Fill first fragment on the FAT if needed */
        if (res == FR_OK) {
          res = fill_last_frag(&fp->obj, fp->clust,
                               0xFFFFFFFF); /* Fill last fragment on the FAT if needed */
        }
        if (res == FR_OK) {
          DIR dj;
          DEF_NAMBUF

          INIT_NAMBUF(fs);
          res = load_obj_xdir(&dj, &fp->obj); /* Load directory entry block */
          if (res == FR_OK) {
            fs->dirbuf[XDIR_Attr] |=
                AM_ARC; /* Set archive attribute to indicate that the file has been changed */
            fs->dirbuf[XDIR_GenFlags] = fp->obj.stat | 1; /* Update file allocation information */
            st_dword(fs->dirbuf + XDIR_FstClus, fp->obj.sclust);   /* Update start cluster */
            st_qword(fs->dirbuf + XDIR_FileSize, fp->obj.objsize); /* Update file size */
            st_qword(fs->dirbuf + XDIR_ValidFileSize,
                     fp->obj.objsize); /* (FatFs does not support Valid File Size feature) */
            st_dword(fs->dirbuf + XDIR_ModTime, tm); /* Update modified time */
            fs->dirbuf[XDIR_ModTime10] = 0;
            st_dword(fs->dirbuf + XDIR_AccTime, 0);
            res = store_xdir(&dj); /* Restore it to the directory */
            if (res == FR_OK) {
              res       = sync_fs(fs);
              fp->flag &= (byte)~FA_MODIFIED;
            }
          }
          FREE_NAMBUF();
        }
      } else
#  endif
      {
        res = move_window(fs, fp->dir_sect);
        if (res == FR_OK) {
          dir = fp->dir_ptr;
          dir[DIR_Attr] |=
              AM_ARC; /* Set archive attribute to indicate that the file has been changed */
          st_clust(fp->obj.fs, dir, fp->obj.sclust); /* Update file allocation information  */
          st_dword(dir + DIR_FileSize, (u32)fp->obj.objsize); /* Update file size */
          st_dword(dir + DIR_ModTime, tm);                    /* Update modified time */
          st_word(dir + DIR_LstAccDate, 0);
          fs->wflag  = 1;
          res        = sync_fs(fs); /* Restore it to the directory */
          fp->flag  &= (byte)~FA_MODIFIED;
        }
      }
    }
  }

  LEAVE_FF(fs, res);
}

#endif /* !FF_FS_READONLY */

/*-----------------------------------------------------------------------*/
/* Close File                                                            */
/*-----------------------------------------------------------------------*/

FRESULT f_close(FIL *fp /* Open file to be closed */
) {
  FRESULT res;
  FATFS  *fs;

#if !FF_FS_READONLY
  res = f_sync(fp); /* Flush cached data */
  if (res == FR_OK)
#endif
  {
    res = validate(&fp->obj, &fs); /* Lock volume */
    if (res == FR_OK) {
#if FF_FS_LOCK
      res = dec_share(fp->obj.lockid);  /* Decrement file open counter */
      if (res == FR_OK) fp->obj.fs = 0; /* Invalidate file object */
#else
      fp->obj.fs = 0; /* Invalidate file object */
#endif
#if FF_FS_REENTRANT
      unlock_volume(fs, FR_OK); /* Unlock volume */
#endif
    }
  }
  return res;
}

#if FF_FS_RPATH >= 1
/*-----------------------------------------------------------------------*/
/* Change Current Directory or Current Drive, Get Current Directory      */
/*-----------------------------------------------------------------------*/

FRESULT f_chdrive(const TCHAR *path /* Drive number to set */
) {
  int vol;

  /* Get logical drive number */
  vol = get_ldnumber(&path);
  if (vol < 0) return FR_INVALID_DRIVE;
  CurrVol = (byte)vol; /* Set it as current volume */

  return FR_OK;
}

FRESULT f_chdir(const TCHAR *path /* Pointer to the directory path */
) {
#  if FF_STR_VOLUME_ID == 2
  uint i;
#  endif
  FRESULT res;
  DIR     dj;
  FATFS  *fs;
  DEF_NAMBUF

  /* Get logical drive */
  res = mount_volume(&path, &fs, 0);
  if (res == FR_OK) {
    dj.obj.fs = fs;
    INIT_NAMBUF(fs);
    res = follow_path(&dj, path);      /* Follow the path */
    if (res == FR_OK) {                /* Follow completed */
      if (dj.fn[NSFLAG] & NS_NONAME) { /* Is it the start directory itself? */
        fs->cdir = dj.obj.sclust;
#  if FF_FS_EXFAT
        if (fs->fs_type == FS_EXFAT) {
          fs->cdc_scl  = dj.obj.c_scl;
          fs->cdc_size = dj.obj.c_size;
          fs->cdc_ofs  = dj.obj.c_ofs;
        }
#  endif
      } else {
        if (dj.obj.attr & AM_DIR) { /* It is a sub-directory */
#  if FF_FS_EXFAT
          if (fs->fs_type == FS_EXFAT) {
            fs->cdir     = ld_dword(fs->dirbuf + XDIR_FstClus); /* Sub-directory cluster */
            fs->cdc_scl  = dj.obj.sclust; /* Save containing directory information */
            fs->cdc_size = ((u32)dj.obj.objsize & 0xFFFFFF00) | dj.obj.stat;
            fs->cdc_ofs  = dj.blk_ofs;
          } else
#  endif
          {
            fs->cdir = ld_clust(fs, dj.dir); /* Sub-directory cluster */
          }
        } else {
          res = FR_NO_PATH; /* Reached but a file */
        }
      }
    }
    FREE_NAMBUF();
    if (res == FR_NO_FILE) res = FR_NO_PATH;
#  if FF_STR_VOLUME_ID == 2 /* Also current drive is changed if in Unix style volume ID */
    if (res == FR_OK) {
      for (i = FF_VOLUMES - 1; i && fs != FatFs[i]; i--)
        ; /* Set current drive */
      CurrVol = (byte)i;
    }
#  endif
  }

  LEAVE_FF(fs, res);
}

#  if FF_FS_RPATH >= 2
FRESULT f_getcwd(TCHAR *buff, /* Pointer to the directory path */
                 uint   len   /* Size of buff in unit of TCHAR */
) {
  FRESULT res;
  DIR     dj;
  FATFS  *fs;
  uint    i, n;
  u32     ccl;
  TCHAR  *tp = buff;
#    if FF_VOLUMES >= 2
  uint vl;
#      if FF_STR_VOLUME_ID
  const char *vp;
#      endif
#    endif
  FILINFO fno;
  DEF_NAMBUF

  /* Get logical drive */
  buff[0] = 0;                                           /* Set null string to get current volume */
  res     = mount_volume((const TCHAR **)&buff, &fs, 0); /* Get current volume */
  if (res == FR_OK) {
    dj.obj.fs = fs;
    INIT_NAMBUF(fs);

    /* Follow parent directories and create the path */
    i = len; /* Bottom of buffer (directory stack base) */
    if (!FF_FS_EXFAT ||
        fs->fs_type != FS_EXFAT) { /* (Cannot do getcwd on exFAT and returns root path) */
      dj.obj.sclust = fs->cdir;    /* Start to follow upper directory from current directory */
      while ((ccl = dj.obj.sclust) != 0) { /* Repeat while current directory is a sub-directory */
        res = dir_sdi(&dj, 1 * SZDIRE);    /* Get parent directory */
        if (res != FR_OK) break;
        res = move_window(fs, dj.sect);
        if (res != FR_OK) break;
        dj.obj.sclust = ld_clust(fs, dj.dir); /* Goto parent directory */
        res           = dir_sdi(&dj, 0);
        if (res != FR_OK) break;
        do { /* Find the entry links to the child directory */
          res = DIR_READ_FILE(&dj);
          if (res != FR_OK) break;
          if (ccl == ld_clust(fs, dj.dir)) break; /* Found the entry */
          res = dir_next(&dj, 0);
        } while (res == FR_OK);
        if (res == FR_NO_FILE) res = FR_INT_ERR; /* It cannot be 'not found'. */
        if (res != FR_OK) break;
        get_fileinfo(&dj, &fno); /* Get the directory name and push it to the buffer */
        for (n = 0; fno.fname[n]; n++)
          ;              /* Name length */
        if (i < n + 1) { /* Insufficient space to store the path name? */
          res = FR_NOT_ENOUGH_CORE;
          break;
        }
        while (n)
          buff[--i] = fno.fname[--n]; /* Stack the name */
        buff[--i] = '/';
      }
    }
    if (res == FR_OK) {
      if (i == len) buff[--i] = '/'; /* Is it the root-directory? */
#    if FF_VOLUMES >= 2              /* Put drive prefix */
      vl = 0;
#      if FF_STR_VOLUME_ID >= 1 /* String volume ID */
      for (n = 0, vp = (const char *)VolumeStr[CurrVol]; vp[n]; n++)
        ;
      if (i >= n + 2) {
        if (FF_STR_VOLUME_ID == 2) *tp++ = (TCHAR)'/';
        for (vl = 0; vl < n; *tp++ = (TCHAR)vp[vl], vl++)
          ;
        if (FF_STR_VOLUME_ID == 1) *tp++ = (TCHAR)':';
        vl++;
      }
#      else /* Numeric volume ID */
      if (i >= 3) {
        *tp++ = (TCHAR)'0' + CurrVol;
        *tp++ = (TCHAR)':';
        vl    = 2;
      }
#      endif
      if (vl == 0) res = FR_NOT_ENOUGH_CORE;
#    endif
      /* Add current directory path */
      if (res == FR_OK) {
        do { /* Copy stacked path string */
          *tp++ = buff[i++];
        } while (i < len);
      }
    }
    FREE_NAMBUF();
  }

  *tp = 0;
  LEAVE_FF(fs, res);
}

#  endif /* FF_FS_RPATH >= 2 */
#endif   /* FF_FS_RPATH >= 1 */

#if FF_FS_MINIMIZE <= 2
/*-----------------------------------------------------------------------*/
/* Seek File Read/Write Pointer                                          */
/*-----------------------------------------------------------------------*/

FRESULT f_lseek(FIL    *fp, /* Pointer to the file object */
                FSIZE_t ofs /* File pointer from top of file */
) {
  FRESULT res;
  FATFS  *fs;
  u32     clst, bcs;
  LBA_t   nsect;
  FSIZE_t ifptr;
#  if FF_USE_FASTSEEK
  u32   cl, pcl, ncl, tcl, tlen, ulen;
  u32  *tbl;
  LBA_t dsc;
#  endif

  res = validate(&fp->obj, &fs); /* Check validity of the file object */
  if (res == FR_OK) res = (FRESULT)fp->err;
#  if FF_FS_EXFAT && !FF_FS_READONLY
  if (res == FR_OK && fs->fs_type == FS_EXFAT) {
    res = fill_last_frag(&fp->obj, fp->clust,
                         0xFFFFFFFF); /* Fill last fragment on the FAT if needed */
  }
#  endif
  if (res != FR_OK) LEAVE_FF(fs, res);

#  if FF_USE_FASTSEEK
  if (fp->cltbl) {               /* Fast seek */
    if (ofs == CREATE_LINKMAP) { /* Create CLMT */
      tbl  = fp->cltbl;
      tlen = *tbl++;
      ulen = 2;              /* Given table size and required table size */
      cl   = fp->obj.sclust; /* Origin of the chain */
      if (cl != 0) {
        do {
          /* Get a fragment */
          tcl   = cl;
          ncl   = 0;
          ulen += 2; /* Top, length and used items */
          do {
            pcl = cl;
            ncl++;
            cl = get_fat(&fp->obj, cl);
            if (cl <= 1) ABORT(fs, FR_INT_ERR);
            if (cl == 0xFFFFFFFF) ABORT(fs, FR_DISK_ERR);
          } while (cl == pcl + 1);
          if (ulen <= tlen) { /* Store the length and top of the fragment */
            *tbl++ = ncl;
            *tbl++ = tcl;
          }
        } while (cl < fs->n_fatent); /* Repeat until end of chain */
      }
      *fp->cltbl = ulen; /* Number of items used */
      if (ulen <= tlen) {
        *tbl = 0; /* Terminate table */
      } else {
        res = FR_NOT_ENOUGH_CORE; /* Given table size is smaller than required */
      }
    } else {                                            /* Fast seek */
      if (ofs > fp->obj.objsize) ofs = fp->obj.objsize; /* Clip offset at the file size */
      fp->fptr = ofs;                                   /* Set file pointer */
      if (ofs > 0) {
        fp->clust = clmt_clust(fp, ofs - 1);
        dsc       = clst2sect(fs, fp->clust);
        if (dsc == 0) ABORT(fs, FR_INT_ERR);
        dsc += (u32)((ofs - 1) / SS(fs)) & (fs->csize - 1);
        if (fp->fptr % SS(fs) && dsc != fp->sect) { /* Refill sector cache if needed */
#    if !FF_FS_TINY
#      if !FF_FS_READONLY
          if (fp->flag & FA_DIRTY) { /* Write-back dirty sector cache */
            if (disk_write(fs->pdrv, fp->buf, fp->sect, 1) != RES_OK) ABORT(fs, FR_DISK_ERR);
            fp->flag &= (byte)~FA_DIRTY;
          }
#      endif
          if (disk_read(fs->pdrv, fp->buf, dsc, 1) != RES_OK)
            ABORT(fs, FR_DISK_ERR); /* Load current sector */
#    endif
          fp->sect = dsc;
        }
      }
    }
  } else
#  endif

  /* Normal Seek */
  {
#  if FF_FS_EXFAT
    if (fs->fs_type != FS_EXFAT && ofs >= 0x100000000)
      ofs = 0xFFFFFFFF; /* Clip at 4 GiB - 1 if at FATxx */
#  endif
    if (ofs > fp->obj.objsize &&
        (FF_FS_READONLY ||
         !(fp->flag & FA_WRITE))) { /* In read-only mode, clip offset with the file size */
      ofs = fp->obj.objsize;
    }
    ifptr    = fp->fptr;
    fp->fptr = nsect = 0;
    if (ofs > 0) {
      bcs = (u32)fs->csize * SS(fs); /* Cluster size (byte) */
      if (ifptr > 0 &&
          (ofs - 1) / bcs >= (ifptr - 1) / bcs) {      /* When seek to same or following cluster, */
        fp->fptr  = (ifptr - 1) & ~(FSIZE_t)(bcs - 1); /* start from the current cluster */
        ofs      -= fp->fptr;
        clst      = fp->clust;
      } else {                 /* When seek to back cluster, */
        clst = fp->obj.sclust; /* start from the first cluster */
#  if !FF_FS_READONLY
        if (clst == 0) { /* If no cluster chain, create a new chain */
          clst = create_chain(&fp->obj, 0);
          if (clst == 1) ABORT(fs, FR_INT_ERR);
          if (clst == 0xFFFFFFFF) ABORT(fs, FR_DISK_ERR);
          fp->obj.sclust = clst;
        }
#  endif
        fp->clust = clst;
      }
      if (clst != 0) {
        while (ofs > bcs) { /* Cluster following loop */
          ofs      -= bcs;
          fp->fptr += bcs;
#  if !FF_FS_READONLY
          if (fp->flag & FA_WRITE) { /* Check if in write mode or not */
            if (FF_FS_EXFAT &&
                fp->fptr >
                    fp->obj
                        .objsize) { /* No FAT chain object needs correct objsize to generate FAT value */
              fp->obj.objsize  = fp->fptr;
              fp->flag        |= FA_MODIFIED;
            }
            clst = create_chain(&fp->obj, clst); /* Follow chain with forceed stretch */
            if (clst == 0) {                     /* Clip file size in case of disk full */
              ofs = 0;
              break;
            }
          } else
#  endif
          {
            clst = get_fat(&fp->obj, clst); /* Follow cluster chain if not in write mode */
          }
          if (clst == 0xFFFFFFFF) ABORT(fs, FR_DISK_ERR);
          if (clst <= 1 || clst >= fs->n_fatent) ABORT(fs, FR_INT_ERR);
          fp->clust = clst;
        }
        fp->fptr += ofs;
        if (ofs % SS(fs)) {
          nsect = clst2sect(fs, clst); /* Current sector */
          if (nsect == 0) ABORT(fs, FR_INT_ERR);
          nsect += (u32)(ofs / SS(fs));
        }
      }
    }
    if (!FF_FS_READONLY &&
        fp->fptr > fp->obj.objsize) { /* Set file change flag if the file size is extended */
      fp->obj.objsize  = fp->fptr;
      fp->flag        |= FA_MODIFIED;
    }
    if (fp->fptr % SS(fs) && nsect != fp->sect) { /* Fill sector cache if needed */
#  if !FF_FS_TINY
#    if !FF_FS_READONLY
      if (fp->flag & FA_DIRTY) { /* Write-back dirty sector cache */
        if (disk_write(fs->pdrv, fp->buf, fp->sect, 1) != RES_OK) ABORT(fs, FR_DISK_ERR);
        fp->flag &= (byte)~FA_DIRTY;
      }
#    endif
      if (disk_read(fs->pdrv, fp->buf, nsect, 1) != RES_OK)
        ABORT(fs, FR_DISK_ERR); /* Fill sector cache */
#  endif
      fp->sect = nsect;
    }
  }

  LEAVE_FF(fs, res);
}

#  if FF_FS_MINIMIZE <= 1
/*-----------------------------------------------------------------------*/
/* Create a Directory Object                                             */
/*-----------------------------------------------------------------------*/

FRESULT f_opendir(DIR         *dp,  /* Pointer to directory object to create */
                  const TCHAR *path /* Pointer to the directory path */
) {
  FRESULT res;
  FATFS  *fs;
  DEF_NAMBUF

  if (!dp) return FR_INVALID_OBJECT;

  /* Get logical drive */
  res = mount_volume(&path, &fs, 0);
  if (res == FR_OK) {
    dp->obj.fs = fs;
    INIT_NAMBUF(fs);
    res = follow_path(dp, path);           /* Follow the path to the directory */
    if (res == FR_OK) {                    /* Follow completed */
      if (!(dp->fn[NSFLAG] & NS_NONAME)) { /* It is not the origin directory itself */
        if (dp->obj.attr & AM_DIR) {       /* This object is a sub-directory */
#    if FF_FS_EXFAT
          if (fs->fs_type == FS_EXFAT) {
            dp->obj.c_scl  = dp->obj.sclust; /* Get containing directory inforamation */
            dp->obj.c_size = ((u32)dp->obj.objsize & 0xFFFFFF00) | dp->obj.stat;
            dp->obj.c_ofs  = dp->blk_ofs;
            init_alloc_info(fs, &dp->obj); /* Get object allocation info */
          } else
#    endif
          {
            dp->obj.sclust = ld_clust(fs, dp->dir); /* Get object allocation info */
          }
        } else { /* This object is a file */
          res = FR_NO_PATH;
        }
      }
      if (res == FR_OK) {
        dp->obj.id = fs->id;
        res        = dir_sdi(dp, 0); /* Rewind directory */
#    if FF_FS_LOCK
        if (res == FR_OK) {
          if (dp->obj.sclust != 0) {
            dp->obj.lockid = inc_share(dp, 0); /* Lock the sub directory */
            if (!dp->obj.lockid) res = FR_TOO_MANY_OPEN_FILES;
          } else {
            dp->obj.lockid = 0; /* Root directory need not to be locked */
          }
        }
#    endif
      }
    }
    FREE_NAMBUF();
    if (res == FR_NO_FILE) res = FR_NO_PATH;
  }
  if (res != FR_OK) dp->obj.fs = 0; /* Invalidate the directory object if function failed */

  LEAVE_FF(fs, res);
}

/*-----------------------------------------------------------------------*/
/* Close Directory                                                       */
/*-----------------------------------------------------------------------*/

FRESULT f_closedir(DIR *dp /* Pointer to the directory object to be closed */
) {
  FRESULT res;
  FATFS  *fs;

  res = validate(&dp->obj, &fs); /* Check validity of the file object */
  if (res == FR_OK) {
#    if FF_FS_LOCK
    if (dp->obj.lockid) res = dec_share(dp->obj.lockid); /* Decrement sub-directory open counter */
    if (res == FR_OK) dp->obj.fs = 0;                    /* Invalidate directory object */
#    else
    dp->obj.fs = 0; /* Invalidate directory object */
#    endif
#    if FF_FS_REENTRANT
    unlock_volume(fs, FR_OK); /* Unlock volume */
#    endif
  }
  return res;
}

/*-----------------------------------------------------------------------*/
/* Read Directory Entries in Sequence                                    */
/*-----------------------------------------------------------------------*/

FRESULT f_readdir(DIR     *dp, /* Pointer to the open directory object */
                  FILINFO *fno /* Pointer to file information to return */
) {
  FRESULT res;
  FATFS  *fs;
  DEF_NAMBUF

  res = validate(&dp->obj, &fs); /* Check validity of the directory object */
  if (res == FR_OK) {
    if (!fno) {
      res = dir_sdi(dp, 0); /* Rewind the directory object */
    } else {
      INIT_NAMBUF(fs);
      res = DIR_READ_FILE(dp);              /* Read an item */
      if (res == FR_NO_FILE) res = FR_OK;   /* Ignore end of directory */
      if (res == FR_OK) {                   /* A valid entry is found */
        get_fileinfo(dp, fno);              /* Get the object information */
        res = dir_next(dp, 0);              /* Increment index for next */
        if (res == FR_NO_FILE) res = FR_OK; /* Ignore end of directory now */
      }
      FREE_NAMBUF();
    }
  }
  LEAVE_FF(fs, res);
}

#    if FF_USE_FIND
/*-----------------------------------------------------------------------*/
/* Find Next File                                                        */
/*-----------------------------------------------------------------------*/

FRESULT f_findnext(DIR     *dp, /* Pointer to the open directory object */
                   FILINFO *fno /* Pointer to the file information structure */
) {
  FRESULT res;

  for (;;) {
    res = f_readdir(dp, fno); /* Get a directory item */
    if (res != FR_OK || !fno || !fno->fname[0])
      break; /* Terminate if any error or end of directory */
    if (pattern_match(dp->pat, fno->fname, 0, FIND_RECURS)) break; /* Test for the file name */
#      if FF_USE_LFN && FF_USE_FIND == 2
    if (pattern_match(dp->pat, fno->altname, 0, FIND_RECURS))
      break; /* Test for alternative name if exist */
#      endif
  }
  return res;
}

/*-----------------------------------------------------------------------*/
/* Find First File                                                       */
/*-----------------------------------------------------------------------*/

FRESULT f_findfirst(DIR         *dp,     /* Pointer to the blank directory object */
                    FILINFO     *fno,    /* Pointer to the file information structure */
                    const TCHAR *path,   /* Pointer to the directory to open */
                    const TCHAR *pattern /* Pointer to the matching pattern */
) {
  FRESULT res;

  dp->pat = pattern;             /* Save pointer to pattern string */
  res     = f_opendir(dp, path); /* Open the target directory */
  if (res == FR_OK) { res = f_findnext(dp, fno); /* Find the first item */ }
  return res;
}

#    endif /* FF_USE_FIND */

#    if FF_FS_MINIMIZE == 0
/*-----------------------------------------------------------------------*/
/* Get File Status                                                       */
/*-----------------------------------------------------------------------*/

FRESULT f_stat(const TCHAR *path, /* Pointer to the file path */
               FILINFO     *fno   /* Pointer to file information to return */
) {
  FRESULT res;
  DIR     dj;
  DEF_NAMBUF

  /* Get logical drive */
  res = mount_volume(&path, &dj.obj.fs, 0);
  if (res == FR_OK) {
    INIT_NAMBUF(dj.obj.fs);
    res = follow_path(&dj, path);      /* Follow the file path */
    if (res == FR_OK) {                /* Follow completed */
      if (dj.fn[NSFLAG] & NS_NONAME) { /* It is origin directory */
        res = FR_INVALID_NAME;
      } else { /* Found an object */
        if (fno) get_fileinfo(&dj, fno);
      }
    }
    FREE_NAMBUF();
  }

  LEAVE_FF(dj.obj.fs, res);
}

#      if !FF_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Get Number of Free Clusters                                           */
/*-----------------------------------------------------------------------*/

FRESULT f_getfree(const TCHAR *path,  /* Logical drive number */
                  u32         *nclst, /* Pointer to a variable to return number of free clusters */
                  FATFS **fatfs /* Pointer to return pointer to corresponding filesystem object */
) {
  FRESULT res;
  FATFS  *fs;
  u32     nfree, clst, stat;
  LBA_t   sect;
  uint    i;
  FFOBJID obj;

  /* Get logical drive */
  res = mount_volume(&path, &fs, 0);
  if (res == FR_OK) {
    *fatfs = fs; /* Return ptr to the fs object */
    /* If free_clst is valid, return it without full FAT scan */
    if (fs->free_clst <= fs->n_fatent - 2) {
      *nclst = fs->free_clst;
    } else {
      /* Scan FAT to obtain number of free clusters */
      nfree = 0;
      if (fs->fs_type == FS_FAT12) { /* FAT12: Scan bit field FAT entries */
        clst   = 2;
        obj.fs = fs;
        do {
          stat = get_fat(&obj, clst);
          if (stat == 0xFFFFFFFF) {
            res = FR_DISK_ERR;
            break;
          }
          if (stat == 1) {
            res = FR_INT_ERR;
            break;
          }
          if (stat == 0) nfree++;
        } while (++clst < fs->n_fatent);
      } else {
#        if FF_FS_EXFAT
        if (fs->fs_type == FS_EXFAT) { /* exFAT: Scan allocation bitmap */
          byte bm;
          uint b;

          clst = fs->n_fatent - 2; /* Number of clusters */
          sect = fs->bitbase;      /* Bitmap sector */
          i    = 0;                /* Offset in the sector */
          do {                     /* Counts numbuer of bits with zero in the bitmap */
            if (i == 0) {          /* New sector? */
              res = move_window(fs, sect++);
              if (res != FR_OK) break;
            }
            for (b = 8, bm = ~fs->win[i]; b && clst; b--, clst--) {
              nfree  += bm & 1;
              bm    >>= 1;
            }
            i = (i + 1) % SS(fs);
          } while (clst);
        } else
#        endif
        {                      /* FAT16/32: Scan u16/u32 FAT entries */
          clst = fs->n_fatent; /* Number of entries */
          sect = fs->fatbase;  /* Top of the FAT */
          i    = 0;            /* Offset in the sector */
          do {                 /* Counts numbuer of entries with zero in the FAT */
            if (i == 0) {      /* New sector? */
              res = move_window(fs, sect++);
              if (res != FR_OK) break;
            }
            if (fs->fs_type == FS_FAT16) {
              if (ld_word(fs->win + i) == 0) nfree++;
              i += 2;
            } else {
              if ((ld_dword(fs->win + i) & 0x0FFFFFFF) == 0) nfree++;
              i += 4;
            }
            i %= SS(fs);
          } while (--clst);
        }
      }
      if (res == FR_OK) {       /* Update parameters if succeeded */
        *nclst         = nfree; /* Return the free clusters */
        fs->free_clst  = nfree; /* Now free_clst is valid */
        fs->fsi_flag  |= 1;     /* FAT32: FSInfo is to be updated */
      }
    }
  }

  LEAVE_FF(fs, res);
}

/*-----------------------------------------------------------------------*/
/* Truncate File                                                         */
/*-----------------------------------------------------------------------*/

FRESULT f_truncate(FIL *fp /* Pointer to the file object */
) {
  FRESULT res;
  FATFS  *fs;
  u32     ncl;

  res = validate(&fp->obj, &fs); /* Check validity of the file object */
  if (res != FR_OK || (res = (FRESULT)fp->err) != FR_OK) LEAVE_FF(fs, res);
  if (!(fp->flag & FA_WRITE)) LEAVE_FF(fs, FR_DENIED); /* Check access mode */

  if (fp->fptr < fp->obj.objsize) { /* Process when fptr is not on the eof */
    if (fp->fptr == 0) {            /* When set file size to zero, remove entire cluster chain */
      res            = remove_chain(&fp->obj, fp->obj.sclust, 0);
      fp->obj.sclust = 0;
    } else { /* When truncate a part of the file, remove remaining clusters */
      ncl = get_fat(&fp->obj, fp->clust);
      res = FR_OK;
      if (ncl == 0xFFFFFFFF) res = FR_DISK_ERR;
      if (ncl == 1) res = FR_INT_ERR;
      if (res == FR_OK && ncl < fs->n_fatent) { res = remove_chain(&fp->obj, ncl, fp->clust); }
    }
    fp->obj.objsize  = fp->fptr; /* Set file size to current read/write point */
    fp->flag        |= FA_MODIFIED;
#        if !FF_FS_TINY
    if (res == FR_OK && (fp->flag & FA_DIRTY)) {
      if (disk_write(fs->pdrv, fp->buf, fp->sect, 1) != RES_OK) {
        res = FR_DISK_ERR;
      } else {
        fp->flag &= (byte)~FA_DIRTY;
      }
    }
#        endif
    if (res != FR_OK) ABORT(fs, res);
  }

  LEAVE_FF(fs, res);
}

/*-----------------------------------------------------------------------*/
/* Delete a File/Directory                                               */
/*-----------------------------------------------------------------------*/

FRESULT f_unlink(const TCHAR *path /* Pointer to the file or directory path */
) {
  FRESULT res;
  FATFS  *fs;
  DIR     dj, sdj;
  u32     dclst = 0;
#        if FF_FS_EXFAT
  FFOBJID obj;
#        endif
  DEF_NAMBUF

  /* Get logical drive */
  res = mount_volume(&path, &fs, FA_WRITE);
  if (res == FR_OK) {
    dj.obj.fs = fs;
    INIT_NAMBUF(fs);
    res = follow_path(&dj, path); /* Follow the file path */
    if (FF_FS_RPATH && res == FR_OK && (dj.fn[NSFLAG] & NS_DOT)) {
      res = FR_INVALID_NAME; /* Cannot remove dot entry */
    }
#        if FF_FS_LOCK
    if (res == FR_OK) res = chk_share(&dj, 2); /* Check if it is an open object */
#        endif
    if (res == FR_OK) { /* The object is accessible */
      if (dj.fn[NSFLAG] & NS_NONAME) {
        res = FR_INVALID_NAME; /* Cannot remove the origin directory */
      } else {
        if (dj.obj.attr & AM_RDO) { res = FR_DENIED; /* Cannot remove R/O object */ }
      }
      if (res == FR_OK) {
#        if FF_FS_EXFAT
        obj.fs = fs;
        if (fs->fs_type == FS_EXFAT) {
          init_alloc_info(fs, &obj);
          dclst = obj.sclust;
        } else
#        endif
        {
          dclst = ld_clust(fs, dj.dir);
        }
        if (dj.obj.attr & AM_DIR) { /* Is it a sub-directory? */
#        if FF_FS_RPATH != 0
          if (dclst == fs->cdir) { /* Is it the current directory? */
            res = FR_DENIED;
          } else
#        endif
          {
            sdj.obj.fs     = fs; /* Open the sub-directory */
            sdj.obj.sclust = dclst;
#        if FF_FS_EXFAT
            if (fs->fs_type == FS_EXFAT) {
              sdj.obj.objsize = obj.objsize;
              sdj.obj.stat    = obj.stat;
            }
#        endif
            res = dir_sdi(&sdj, 0);
            if (res == FR_OK) {
              res = DIR_READ_FILE(&sdj);          /* Test if the directory is empty */
              if (res == FR_OK) res = FR_DENIED;  /* Not empty? */
              if (res == FR_NO_FILE) res = FR_OK; /* Empty? */
            }
          }
        }
      }
      if (res == FR_OK) {
        res = dir_remove(&dj);            /* Remove the directory entry */
        if (res == FR_OK && dclst != 0) { /* Remove the cluster chain if exist */
#        if FF_FS_EXFAT
          res = remove_chain(&obj, dclst, 0);
#        else
          res = remove_chain(&dj.obj, dclst, 0);
#        endif
        }
        if (res == FR_OK) res = sync_fs(fs);
      }
    }
    FREE_NAMBUF();
  }

  LEAVE_FF(fs, res);
}

/*-----------------------------------------------------------------------*/
/* Create a Directory                                                    */
/*-----------------------------------------------------------------------*/

FRESULT f_mkdir(const TCHAR *path /* Pointer to the directory path */
) {
  FRESULT res;
  FATFS  *fs;
  DIR     dj;
  FFOBJID sobj;
  u32     dcl, pcl, tm;
  DEF_NAMBUF

  res = mount_volume(&path, &fs, FA_WRITE); /* Get logical drive */
  if (res == FR_OK) {
    dj.obj.fs = fs;
    INIT_NAMBUF(fs);
    res = follow_path(&dj, path);                                       /* Follow the file path */
    if (res == FR_OK) res = FR_EXIST;                                   /* Name collision? */
    if (FF_FS_RPATH && res == FR_NO_FILE && (dj.fn[NSFLAG] & NS_DOT)) { /* Invalid name? */
      res = FR_INVALID_NAME;
    }
    if (res == FR_NO_FILE) {            /* It is clear to create a new directory */
      sobj.fs = fs;                     /* New object id to create a new chain */
      dcl     = create_chain(&sobj, 0); /* Allocate a cluster for the new directory */
      res     = FR_OK;
      if (dcl == 0) res = FR_DENIED;            /* No space to allocate a new cluster? */
      if (dcl == 1) res = FR_INT_ERR;           /* Any insanity? */
      if (dcl == 0xFFFFFFFF) res = FR_DISK_ERR; /* Disk error? */
      tm = GET_FATTIME();
      if (res == FR_OK) {
        res = dir_clear(fs, dcl); /* Clean up the new table */
        if (res == FR_OK) {
          if (!FF_FS_EXFAT || fs->fs_type != FS_EXFAT) { /* Create dot entries (FAT only) */
            memset(fs->win + DIR_Name, ' ', 11);         /* Create "." entry */
            fs->win[DIR_Name] = '.';
            fs->win[DIR_Attr] = AM_DIR;
            st_dword(fs->win + DIR_ModTime, tm);
            st_clust(fs, fs->win, dcl);
            memcpy(fs->win + SZDIRE, fs->win, SZDIRE); /* Create ".." entry */
            fs->win[SZDIRE + 1] = '.';
            pcl                 = dj.obj.sclust;
            st_clust(fs, fs->win + SZDIRE, pcl);
            fs->wflag = 1;
          }
          res = dir_register(&dj); /* Register the object to the parent directoy */
        }
      }
      if (res == FR_OK) {
#        if FF_FS_EXFAT
        if (fs->fs_type == FS_EXFAT) {              /* Initialize directory entry block */
          st_dword(fs->dirbuf + XDIR_ModTime, tm);  /* Created time */
          st_dword(fs->dirbuf + XDIR_FstClus, dcl); /* Table start cluster */
          st_dword(fs->dirbuf + XDIR_FileSize,
                   (u32)fs->csize * SS(fs)); /* Directory size needs to be valid */
          st_dword(fs->dirbuf + XDIR_ValidFileSize, (u32)fs->csize * SS(fs));
          fs->dirbuf[XDIR_GenFlags] = 3;      /* Initialize the object flag */
          fs->dirbuf[XDIR_Attr]     = AM_DIR; /* Attribute */
          res                       = store_xdir(&dj);
        } else
#        endif
        {
          st_dword(dj.dir + DIR_ModTime, tm); /* Created time */
          st_clust(fs, dj.dir, dcl);          /* Table start cluster */
          dj.dir[DIR_Attr] = AM_DIR;          /* Attribute */
          fs->wflag        = 1;
        }
        if (res == FR_OK) { res = sync_fs(fs); }
      } else {
        remove_chain(&sobj, dcl, 0); /* Could not register, remove the allocated cluster */
      }
    }
    FREE_NAMBUF();
  }

  LEAVE_FF(fs, res);
}

/*-----------------------------------------------------------------------*/
/* Rename a File/Directory                                               */
/*-----------------------------------------------------------------------*/

FRESULT f_rename(const TCHAR *path_old, /* Pointer to the object name to be renamed */
                 const TCHAR *path_new  /* Pointer to the new name */
) {
  FRESULT res;
  FATFS  *fs;
  DIR     djo, djn;
  byte    buf[FF_FS_EXFAT ? SZDIRE * 2 : SZDIRE], *dir;
  LBA_t   sect;
  DEF_NAMBUF

  get_ldnumber(&path_new);                      /* Snip the drive number of new name off */
  res = mount_volume(&path_old, &fs, FA_WRITE); /* Get logical drive of the old object */
  if (res == FR_OK) {
    djo.obj.fs = fs;
    INIT_NAMBUF(fs);
    res = follow_path(&djo, path_old); /* Check old object */
    if (res == FR_OK && (djo.fn[NSFLAG] & (NS_DOT | NS_NONAME)))
      res = FR_INVALID_NAME; /* Check validity of name */
#        if FF_FS_LOCK
    if (res == FR_OK) { res = chk_share(&djo, 2); }
#        endif
    if (res == FR_OK) { /* Object to be renamed is found */
#        if FF_FS_EXFAT
      if (fs->fs_type == FS_EXFAT) { /* At exFAT volume */
        byte nf, nn;
        u16  nh;

        memcpy(buf, fs->dirbuf, SZDIRE * 2); /* Save 85+C0 entry of old object */
        memcpy(&djn, &djo, sizeof djo);
        res = follow_path(&djn, path_new); /* Make sure if new object name is not in use */
        if (res == FR_OK) {                /* Is new name already in use by any other object? */
          res = (djn.obj.sclust == djo.obj.sclust && djn.dptr == djo.dptr) ? FR_NO_FILE : FR_EXIST;
        }
        if (res == FR_NO_FILE) {    /* It is a valid path and no name collision */
          res = dir_register(&djn); /* Register the new entry */
          if (res == FR_OK) {
            nf = fs->dirbuf[XDIR_NumSec];
            nn = fs->dirbuf[XDIR_NumName];
            nh = ld_word(fs->dirbuf + XDIR_NameHash);
            memcpy(fs->dirbuf, buf, SZDIRE * 2); /* Restore 85+C0 entry */
            fs->dirbuf[XDIR_NumSec]  = nf;
            fs->dirbuf[XDIR_NumName] = nn;
            st_word(fs->dirbuf + XDIR_NameHash, nh);
            if (!(fs->dirbuf[XDIR_Attr] & AM_DIR))
              fs->dirbuf[XDIR_Attr] |= AM_ARC; /* Set archive attribute if it is a file */
            /* Start of critical section where an interruption can cause a cross-link */
            res = store_xdir(&djn);
          }
        }
      } else
#        endif
      {                                    /* At FAT/FAT32 volume */
        memcpy(buf, djo.dir, SZDIRE);      /* Save directory entry of the object */
        memcpy(&djn, &djo, sizeof(DIR));   /* Duplicate the directory object */
        res = follow_path(&djn, path_new); /* Make sure if new object name is not in use */
        if (res == FR_OK) {                /* Is new name already in use by any other object? */
          res = (djn.obj.sclust == djo.obj.sclust && djn.dptr == djo.dptr) ? FR_NO_FILE : FR_EXIST;
        }
        if (res == FR_NO_FILE) {    /* It is a valid path and no name collision */
          res = dir_register(&djn); /* Register the new entry */
          if (res == FR_OK) {
            dir = djn.dir; /* Copy directory entry of the object except name */
            memcpy(dir + 13, buf + 13, SZDIRE - 13);
            dir[DIR_Attr] = buf[DIR_Attr];
            if (!(dir[DIR_Attr] & AM_DIR))
              dir[DIR_Attr] |= AM_ARC; /* Set archive attribute if it is a file */
            fs->wflag = 1;
            if ((dir[DIR_Attr] & AM_DIR) &&
                djo.obj.sclust !=
                    djn.obj.sclust) { /* Update .. entry in the sub-directory if needed */
              sect = clst2sect(fs, ld_clust(fs, dir));
              if (sect == 0) {
                res = FR_INT_ERR;
              } else {
                /* Start of critical section where an interruption can cause a cross-link */
                res = move_window(fs, sect);
                dir = fs->win + SZDIRE * 1; /* Ptr to .. entry */
                if (res == FR_OK && dir[1] == '.') {
                  st_clust(fs, dir, djn.obj.sclust);
                  fs->wflag = 1;
                }
              }
            }
          }
        }
      }
      if (res == FR_OK) {
        res = dir_remove(&djo); /* Remove old entry */
        if (res == FR_OK) { res = sync_fs(fs); }
      }
      /* End of the critical section */
    }
    FREE_NAMBUF();
  }

  LEAVE_FF(fs, res);
}

#      endif /* !FF_FS_READONLY */
#    endif   /* FF_FS_MINIMIZE == 0 */
#  endif     /* FF_FS_MINIMIZE <= 1 */
#endif       /* FF_FS_MINIMIZE <= 2 */

#if FF_USE_CHMOD && !FF_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Change Attribute                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_chmod(const TCHAR *path, /* Pointer to the file path */
                byte         attr, /* Attribute bits */
                byte         mask  /* Attribute mask to change */
) {
  FRESULT res;
  FATFS  *fs;
  DIR     dj;
  DEF_NAMBUF

  res = mount_volume(&path, &fs, FA_WRITE); /* Get logical drive */
  if (res == FR_OK) {
    dj.obj.fs = fs;
    INIT_NAMBUF(fs);
    res = follow_path(&dj, path); /* Follow the file path */
    if (res == FR_OK && (dj.fn[NSFLAG] & (NS_DOT | NS_NONAME)))
      res = FR_INVALID_NAME; /* Check object validity */
    if (res == FR_OK) {
      mask &= AM_RDO | AM_HID | AM_SYS | AM_ARC; /* Valid attribute mask */
#  if FF_FS_EXFAT
      if (fs->fs_type == FS_EXFAT) {
        fs->dirbuf[XDIR_Attr] =
            (attr & mask) | (fs->dirbuf[XDIR_Attr] & (byte)~mask); /* Apply attribute change */
        res = store_xdir(&dj);
      } else
#  endif
      {
        dj.dir[DIR_Attr] =
            (attr & mask) | (dj.dir[DIR_Attr] & (byte)~mask); /* Apply attribute change */
        fs->wflag = 1;
      }
      if (res == FR_OK) { res = sync_fs(fs); }
    }
    FREE_NAMBUF();
  }

  LEAVE_FF(fs, res);
}

/*-----------------------------------------------------------------------*/
/* Change Timestamp                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_utime(const TCHAR   *path, /* Pointer to the file/directory name */
                const FILINFO *fno   /* Pointer to the timestamp to be set */
) {
  FRESULT res;
  FATFS  *fs;
  DIR     dj;
  DEF_NAMBUF

  res = mount_volume(&path, &fs, FA_WRITE); /* Get logical drive */
  if (res == FR_OK) {
    dj.obj.fs = fs;
    INIT_NAMBUF(fs);
    res = follow_path(&dj, path); /* Follow the file path */
    if (res == FR_OK && (dj.fn[NSFLAG] & (NS_DOT | NS_NONAME)))
      res = FR_INVALID_NAME; /* Check object validity */
    if (res == FR_OK) {
#  if FF_FS_EXFAT
      if (fs->fs_type == FS_EXFAT) {
        st_dword(fs->dirbuf + XDIR_ModTime, (u32)fno->fdate << 16 | fno->ftime);
        res = store_xdir(&dj);
      } else
#  endif
      {
        st_dword(dj.dir + DIR_ModTime, (u32)fno->fdate << 16 | fno->ftime);
        fs->wflag = 1;
      }
      if (res == FR_OK) { res = sync_fs(fs); }
    }
    FREE_NAMBUF();
  }

  LEAVE_FF(fs, res);
}

#endif /* FF_USE_CHMOD && !FF_FS_READONLY */

#if FF_USE_LABEL
/*-----------------------------------------------------------------------*/
/* Get Volume Label                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_getlabel(const TCHAR *path,  /* Logical drive number */
                   TCHAR       *label, /* Buffer to store the volume label */
                   u32         *vsn    /* Variable to store the volume serial number */
) {
  FRESULT  res;
  FATFS   *fs;
  DIR      dj;
  uint     si, di;
  char16_t wc;

  /* Get logical drive */
  res = mount_volume(&path, &fs, 0);

  /* Get volume label */
  if (res == FR_OK && label) {
    dj.obj.fs     = fs;
    dj.obj.sclust = 0; /* Open root directory */
    res           = dir_sdi(&dj, 0);
    if (res == FR_OK) {
      res = DIR_READ_LABEL(&dj); /* Find a volume label entry */
      if (res == FR_OK) {
#  if FF_FS_EXFAT
        if (fs->fs_type == FS_EXFAT) {
          char16_t hs;
          uint     nw;

          for (si = di = hs = 0; si < dj.dir[XDIR_NumLabel];
               si++) { /* Extract volume label from 83 entry */
            wc = ld_word(dj.dir + XDIR_Label + si * 2);
            if (hs == 0 && IsSurrogate(wc)) { /* Is the code a surrogate? */
              hs = wc;
              continue;
            }
            nw = put_utf((u32)hs << 16 | wc, &label[di], 4); /* Store it in API encoding */
            if (nw == 0) {                                   /* Encode error? */
              di = 0;
              break;
            }
            di += nw;
            hs  = 0;
          }
          if (hs != 0) di = 0; /* Broken surrogate pair? */
          label[di] = 0;
        } else
#  endif
        {
          si = di = 0; /* Extract volume label from AM_VOL entry */
          while (si < 11) {
            wc = dj.dir[si++];
#  if FF_USE_LFN && FF_LFN_UNICODE >= 1                                    /* Unicode output */
            if (dbc_1st((byte)wc) && si < 11) wc = wc << 8 | dj.dir[si++]; /* Is it a DBC? */
            wc = ff_oem2uni(wc, CODEPAGE); /* Convert it into Unicode */
            if (wc == 0) {                 /* Invalid char in current code page? */
              di = 0;
              break;
            }
            di += put_utf(wc, &label[di], 4); /* Store it in Unicode */
#  else                                       /* ANSI/OEM output */
            label[di++] = (TCHAR)wc;
#  endif
          }
          do { /* Truncate trailing spaces */
            label[di] = 0;
            if (di == 0) break;
          } while (label[--di] == ' ');
        }
      }
    }
    if (res == FR_NO_FILE) { /* No label entry and return nul string */
      label[0] = 0;
      res      = FR_OK;
    }
  }

  /* Get volume serial number */
  if (res == FR_OK && vsn) {
    res = move_window(fs, fs->volbase);
    if (res == FR_OK) {
      switch (fs->fs_type) {
      case FS_EXFAT: di = BPB_VolIDEx; break;

      case FS_FAT32: di = BS_VolID32; break;

      default: di = BS_VolID;
      }
      *vsn = ld_dword(fs->win + di);
    }
  }

  LEAVE_FF(fs, res);
}

#  if !FF_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Set Volume Label                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_setlabel(const TCHAR *label /* Volume label to set with heading logical drive number */
) {
  FRESULT           res;
  FATFS            *fs;
  DIR               dj;
  byte              dirvn[22];
  uint              di;
  char16_t          wc;
  static const char badchr[18] = "+.,;=[]"
                                 "/*:<>|\\\"\?\x7F"; /* [0..16] for FAT, [7..16] for exFAT */
#    if FF_USE_LFN
  u32 dc;
#    endif

  /* Get logical drive */
  res = mount_volume(&label, &fs, FA_WRITE);
  if (res != FR_OK) LEAVE_FF(fs, res);
#    if FF_STR_VOLUME_ID == 2
  for (; *label == '/'; label++)
    ; /* Snip the separators off */
#    endif

#    if FF_FS_EXFAT
  if (fs->fs_type == FS_EXFAT) { /* On the exFAT volume */
    memset(dirvn, 0, 22);
    di = 0;
    while ((uint)*label >= ' ') { /* Create volume label */
      dc = tchar2uni(&label);     /* Get a Unicode character */
      if (dc >= 0x10000) {
        if (dc == 0xFFFFFFFF || di >= 10) { /* Wrong surrogate or buffer overflow */
          dc = 0;
        } else {
          st_word(dirvn + di * 2, (char16_t)(dc >> 16));
          di++;
        }
      }
      if (dc == 0 || strchr(&badchr[7], (int)dc) ||
          di >= 11) { /* Check validity of the volume label */
        LEAVE_FF(fs, FR_INVALID_NAME);
      }
      st_word(dirvn + di * 2, (char16_t)dc);
      di++;
    }
  } else
#    endif
  { /* On the FAT/FAT32 volume */
    memset(dirvn, ' ', 11);
    di = 0;
    while ((uint)*label >= ' ') { /* Create volume label */
#    if FF_USE_LFN
      dc = tchar2uni(&label);
      wc = (dc < 0x10000) ? ff_uni2oem(ff_wtoupper(dc), CODEPAGE) : 0;
#    else /* ANSI/OEM input */
      wc = (byte)*label++;
      if (dbc_1st((byte)wc)) wc = dbc_2nd((byte)*label) ? wc << 8 | (byte)*label++ : 0;
      if (IsLower(wc)) wc -= 0x20; /* To upper ASCII characters */
#      if FF_CODE_PAGE == 0
      if (ExCvt && wc >= 0x80) wc = ExCvt[wc - 0x80]; /* To upper extended characters (SBCS cfg) */
#      elif FF_CODE_PAGE < 900
      if (wc >= 0x80) wc = ExCvt[wc - 0x80]; /* To upper extended characters (SBCS cfg) */
#      endif
#    endif
      if (wc == 0 || strchr(&badchr[0], (int)wc) ||
          di >= (uint)((wc >= 0x100) ? 10 : 11)) { /* Reject invalid characters for volume label */
        LEAVE_FF(fs, FR_INVALID_NAME);
      }
      if (wc >= 0x100) dirvn[di++] = (byte)(wc >> 8);
      dirvn[di++] = (byte)wc;
    }
    if (dirvn[0] == DDEM) LEAVE_FF(fs, FR_INVALID_NAME); /* Reject illegal name (heading DDEM) */
    while (di && dirvn[di - 1] == ' ')
      di--; /* Snip trailing spaces */
  }

  /* Set volume label */
  dj.obj.fs     = fs;
  dj.obj.sclust = 0; /* Open root directory */
  res           = dir_sdi(&dj, 0);
  if (res == FR_OK) {
    res = DIR_READ_LABEL(&dj); /* Get volume label entry */
    if (res == FR_OK) {
      if (FF_FS_EXFAT && fs->fs_type == FS_EXFAT) {
        dj.dir[XDIR_NumLabel] = (byte)di; /* Change the volume label */
        memcpy(dj.dir + XDIR_Label, dirvn, 22);
      } else {
        if (di != 0) {
          memcpy(dj.dir, dirvn, 11); /* Change the volume label */
        } else {
          dj.dir[DIR_Name] = DDEM; /* Remove the volume label */
        }
      }
      fs->wflag = 1;
      res       = sync_fs(fs);
    } else { /* No volume label entry or an error */
      if (res == FR_NO_FILE) {
        res = FR_OK;
        if (di != 0) {             /* Create a volume label entry */
          res = dir_alloc(&dj, 1); /* Allocate an entry */
          if (res == FR_OK) {
            memset(dj.dir, 0, SZDIRE); /* Clean the entry */
            if (FF_FS_EXFAT && fs->fs_type == FS_EXFAT) {
              dj.dir[XDIR_Type]     = ET_VLABEL; /* Create volume label entry */
              dj.dir[XDIR_NumLabel] = (byte)di;
              memcpy(dj.dir + XDIR_Label, dirvn, 22);
            } else {
              dj.dir[DIR_Attr] = AM_VOL; /* Create volume label entry */
              memcpy(dj.dir, dirvn, 11);
            }
            fs->wflag = 1;
            res       = sync_fs(fs);
          }
        }
      }
    }
  }

  LEAVE_FF(fs, res);
}

#  endif /* !FF_FS_READONLY */
#endif   /* FF_USE_LABEL */

#if FF_USE_EXPAND && !FF_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Allocate a Contiguous Blocks to the File                              */
/*-----------------------------------------------------------------------*/

FRESULT f_expand(FIL    *fp,  /* Pointer to the file object */
                 FSIZE_t fsz, /* File size to be expanded to */
                 byte    opt  /* Operation mode 0:Find and prepare or 1:Find and allocate */
) {
  FRESULT res;
  FATFS  *fs;
  u32     n, clst, stcl, scl, ncl, tcl, lclst;

  res = validate(&fp->obj, &fs); /* Check validity of the file object */
  if (res != FR_OK || (res = (FRESULT)fp->err) != FR_OK) LEAVE_FF(fs, res);
  if (fsz == 0 || fp->obj.objsize != 0 || !(fp->flag & FA_WRITE)) LEAVE_FF(fs, FR_DENIED);
#  if FF_FS_EXFAT
  if (fs->fs_type != FS_EXFAT && fsz >= 0x100000000)
    LEAVE_FF(fs, FR_DENIED); /* Check if in size limit */
#  endif
  n     = (u32)fs->csize * SS(fs);                    /* Cluster size */
  tcl   = (u32)(fsz / n) + ((fsz & (n - 1)) ? 1 : 0); /* Number of clusters required */
  stcl  = fs->last_clst;
  lclst = 0;
  if (stcl < 2 || stcl >= fs->n_fatent) stcl = 2;

#  if FF_FS_EXFAT
  if (fs->fs_type == FS_EXFAT) {
    scl = find_bitmap(fs, stcl, tcl); /* Find a contiguous cluster block */
    if (scl == 0) res = FR_DENIED;    /* No contiguous cluster block was found */
    if (scl == 0xFFFFFFFF) res = FR_DISK_ERR;
    if (res == FR_OK) {                         /* A contiguous free area is found */
      if (opt) {                                /* Allocate it now */
        res   = change_bitmap(fs, scl, tcl, 1); /* Mark the cluster block 'in use' */
        lclst = scl + tcl - 1;
      } else { /* Set it as suggested point for next allocation */
        lclst = scl - 1;
      }
    }
  } else
#  endif
  {
    scl = clst = stcl;
    ncl        = 0;
    for (;;) { /* Find a contiguous cluster block */
      n = get_fat(&fp->obj, clst);
      if (++clst >= fs->n_fatent) clst = 2;
      if (n == 1) {
        res = FR_INT_ERR;
        break;
      }
      if (n == 0xFFFFFFFF) {
        res = FR_DISK_ERR;
        break;
      }
      if (n == 0) {              /* Is it a free cluster? */
        if (++ncl == tcl) break; /* Break if a contiguous cluster block is found */
      } else {
        scl = clst;
        ncl = 0; /* Not a free cluster */
      }
      if (clst == stcl) { /* No contiguous cluster? */
        res = FR_DENIED;
        break;
      }
    }
    if (res == FR_OK) {                             /* A contiguous free area is found */
      if (opt) {                                    /* Allocate it now */
        for (clst = scl, n = tcl; n; clst++, n--) { /* Create a cluster chain on the FAT */
          res = put_fat(fs, clst, (n == 1) ? 0xFFFFFFFF : clst + 1);
          if (res != FR_OK) break;
          lclst = clst;
        }
      } else { /* Set it as suggested point for next allocation */
        lclst = scl - 1;
      }
    }
  }

  if (res == FR_OK) {
    fs->last_clst = lclst;   /* Set suggested start cluster to start next */
    if (opt) {               /* Is it allocated now? */
      fp->obj.sclust  = scl; /* Update object allocation information */
      fp->obj.objsize = fsz;
      if (FF_FS_EXFAT) fp->obj.stat = 2; /* Set status 'contiguous chain' */
      fp->flag |= FA_MODIFIED;
      if (fs->free_clst <= fs->n_fatent - 2) { /* Update FSINFO */
        fs->free_clst -= tcl;
        fs->fsi_flag  |= 1;
      }
    }
  }

  LEAVE_FF(fs, res);
}

#endif /* FF_USE_EXPAND && !FF_FS_READONLY */

#if FF_USE_FORWARD
/*-----------------------------------------------------------------------*/
/* Forward Data to the Stream Directly                                   */
/*-----------------------------------------------------------------------*/

FRESULT f_forward(FIL *fp,                          /* Pointer to the file object */
                  uint (*func)(const byte *, uint), /* Pointer to the streaming function */
                  uint  btf,                        /* Number of bytes to forward */
                  uint *bf                          /* Pointer to number of bytes forwarded */
) {
  FRESULT res;
  FATFS  *fs;
  u32     clst;
  LBA_t   sect;
  FSIZE_t remain;
  uint    rcnt, csect;
  byte   *dbuf;

  *bf = 0;                       /* Clear transfer byte counter */
  res = validate(&fp->obj, &fs); /* Check validity of the file object */
  if (res != FR_OK || (res = (FRESULT)fp->err) != FR_OK) LEAVE_FF(fs, res);
  if (!(fp->flag & FA_READ)) LEAVE_FF(fs, FR_DENIED); /* Check access mode */

  remain = fp->obj.objsize - fp->fptr;
  if (btf > remain) btf = (uint)remain; /* Truncate btf by remaining bytes */

  for (; btf > 0 && (*func)(0, 0);
       fp->fptr += rcnt, *bf += rcnt,
       btf -= rcnt) { /* Repeat until all data transferred or stream goes busy */
    csect = (uint)(fp->fptr / SS(fs) & (fs->csize - 1)); /* Sector offset in the cluster */
    if (fp->fptr % SS(fs) == 0) {                        /* On the sector boundary? */
      if (csect == 0) {                                  /* On the cluster boundary? */
        clst = (fp->fptr == 0) ?                         /* On the top of the file? */
                   fp->obj.sclust
                               : get_fat(&fp->obj, fp->clust);
        if (clst <= 1) ABORT(fs, FR_INT_ERR);
        if (clst == 0xFFFFFFFF) ABORT(fs, FR_DISK_ERR);
        fp->clust = clst; /* Update current cluster */
      }
    }
    sect = clst2sect(fs, fp->clust); /* Get current data sector */
    if (sect == 0) ABORT(fs, FR_INT_ERR);
    sect += csect;
#  if FF_FS_TINY
    if (move_window(fs, sect) != FR_OK)
      ABORT(fs, FR_DISK_ERR); /* Move sector window to the file data */
    dbuf = fs->win;
#  else
    if (fp->sect != sect) { /* Fill sector cache with file data */
#    if !FF_FS_READONLY
      if (fp->flag & FA_DIRTY) { /* Write-back dirty sector cache */
        if (disk_write(fs->pdrv, fp->buf, fp->sect, 1) != RES_OK) ABORT(fs, FR_DISK_ERR);
        fp->flag &= (byte)~FA_DIRTY;
      }
#    endif
      if (disk_read(fs->pdrv, fp->buf, sect, 1) != RES_OK) ABORT(fs, FR_DISK_ERR);
    }
    dbuf = fp->buf;
#  endif
    fp->sect = sect;
    rcnt     = SS(fs) - (uint)fp->fptr % SS(fs); /* Number of bytes remains in the sector */
    if (rcnt > btf) rcnt = btf;                  /* Clip it by btr if needed */
    rcnt = (*func)(dbuf + ((uint)fp->fptr % SS(fs)), rcnt); /* Forward the file data */
    if (rcnt == 0) ABORT(fs, FR_INT_ERR);
  }

  LEAVE_FF(fs, FR_OK);
}
#endif /* FF_USE_FORWARD */

#if !FF_FS_READONLY && FF_USE_MKFS
/*-----------------------------------------------------------------------*/
/* Create FAT/exFAT volume (with sub-functions)                          */
/*-----------------------------------------------------------------------*/

#  define N_SEC_TRACK 63       /* Sectors per track for determination of drive CHS */
#  define GPT_ALIGN   0x100000 /* Alignment of partitions in GPT [byte] (>=128KB) */
#  define GPT_ITEMS   128      /* Number of GPT table size (>=128, sector aligned) */

/* Create partitions on the physical drive in format of MBR or GPT */

static FRESULT create_partition(byte        drv,    /* Physical drive number */
                                const LBA_t plst[], /* Partition list */
                                byte        sys, /* System ID for each partition (for only MBR) */
                                byte       *buf  /* Working buffer for a sector */
) {
  uint  i, cy;
  LBA_t sz_drv;
  u32   sz_drv32, nxt_alloc32, sz_part32;
  byte *pte;
  byte  hd, n_hd, sc, n_sc;

  /* Get physical drive size */
  if (disk_ioctl(drv, GET_SECTOR_COUNT, &sz_drv) != RES_OK) return FR_DISK_ERR;

#  if FF_LBA64
  if (sz_drv >= FF_MIN_GPT) { /* Create partitions in GPT format */
    u16               ss;
    uint              sz_ptbl, pi, si, ofs;
    u32               bcc, rnd, align;
    u64               nxt_alloc, sz_part, sz_pool, top_bpt;
    static const byte gpt_mbr[16] = {0x00, 0x00, 0x02, 0x00, 0xEE, 0xFE, 0xFF, 0x00,
                                     0x01, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF};

#    if FF_MAX_SS != FF_MIN_SS
    if (disk_ioctl(drv, GET_SECTOR_SIZE, &ss) != RES_OK) return FR_DISK_ERR; /* Get sector size */
    if (ss > FF_MAX_SS || ss < FF_MIN_SS || (ss & (ss - 1))) return FR_DISK_ERR;
#    else
    ss = FF_MAX_SS;
#    endif
    rnd       = (u32)sz_drv + GET_FATTIME(); /* Random seed */
    align     = GPT_ALIGN / ss;              /* Partition alignment for GPT [sector] */
    sz_ptbl   = GPT_ITEMS * SZ_GPTE / ss;    /* Size of partition table [sector] */
    top_bpt   = sz_drv - sz_ptbl - 1;        /* Backup partition table start sector */
    nxt_alloc = 2 + sz_ptbl;                 /* First allocatable sector */
    sz_pool   = top_bpt - nxt_alloc;         /* Size of allocatable area */
    bcc       = 0xFFFFFFFF;
    sz_part   = 1;
    pi = si = 0; /* partition table index, size table index */
    do {
      if (pi * SZ_GPTE % ss == 0) memset(buf, 0, ss); /* Clean the buffer if needed */
      if (sz_part != 0) {                             /* Is the size table not termintated? */
        nxt_alloc = (nxt_alloc + align - 1) & ((u64)0 - align); /* Align partition start */
        sz_part   = plst[si++];                                 /* Get a partition size */
        if (sz_part <= 100) {                                   /* Is the size in percentage? */
          sz_part = sz_pool * sz_part / 100;
          sz_part = (sz_part + align - 1) &
                    ((u64)0 - align); /* Align partition end (only if in percentage) */
        }
        if (nxt_alloc + sz_part > top_bpt) { /* Clip the size at end of the pool */
          sz_part = (nxt_alloc < top_bpt) ? top_bpt - nxt_alloc : 0;
        }
      }
      if (sz_part != 0) { /* Add a partition? */
        ofs = pi * SZ_GPTE % ss;
        memcpy(buf + ofs + GPTE_PtGuid, GUID_MS_Basic,
               16); /* Set partition GUID (Microsoft Basic Data) */
        rnd = make_rand(rnd, buf + ofs + GPTE_UpGuid, 16);          /* Set unique partition GUID */
        st_qword(buf + ofs + GPTE_FstLba, nxt_alloc);               /* Set partition start sector */
        st_qword(buf + ofs + GPTE_LstLba, nxt_alloc + sz_part - 1); /* Set partition end sector */
        nxt_alloc += sz_part;                                       /* Next allocatable sector */
      }
      if ((pi + 1) * SZ_GPTE % ss == 0) { /* Write the buffer if it is filled up */
        for (i = 0; i < ss; bcc = crc32(bcc, buf[i++]))
          ; /* Calculate table check sum */
        if (disk_write(drv, buf, 2 + pi * SZ_GPTE / ss, 1) != RES_OK)
          return FR_DISK_ERR; /* Write to primary table */
        if (disk_write(drv, buf, top_bpt + pi * SZ_GPTE / ss, 1) != RES_OK)
          return FR_DISK_ERR; /* Write to secondary table */
      }
    } while (++pi < GPT_ITEMS);

    /* Create primary GPT header */
    memset(buf, 0, ss);
    memcpy(buf + GPTH_Sign,
           "EFI PART"
           "\0\0\1\0"
           "\x5C\0\0",
           16);                                   /* Signature, version (1.0) and size (92) */
    st_dword(buf + GPTH_PtBcc, ~bcc);             /* Table check sum */
    st_qword(buf + GPTH_CurLba, 1);               /* LBA of this header */
    st_qword(buf + GPTH_BakLba, sz_drv - 1);      /* LBA of secondary header */
    st_qword(buf + GPTH_FstLba, 2 + sz_ptbl);     /* LBA of first allocatable sector */
    st_qword(buf + GPTH_LstLba, top_bpt - 1);     /* LBA of last allocatable sector */
    st_dword(buf + GPTH_PteSize, SZ_GPTE);        /* Size of a table entry */
    st_dword(buf + GPTH_PtNum, GPT_ITEMS);        /* Number of table entries */
    st_dword(buf + GPTH_PtOfs, 2);                /* LBA of this table */
    rnd = make_rand(rnd, buf + GPTH_DskGuid, 16); /* Disk GUID */
    for (i = 0, bcc = 0xFFFFFFFF; i < 92; bcc = crc32(bcc, buf[i++]))
      ;                             /* Calculate header check sum */
    st_dword(buf + GPTH_Bcc, ~bcc); /* Header check sum */
    if (disk_write(drv, buf, 1, 1) != RES_OK) return FR_DISK_ERR;

    /* Create secondary GPT header */
    st_qword(buf + GPTH_CurLba, sz_drv - 1); /* LBA of this header */
    st_qword(buf + GPTH_BakLba, 1);          /* LBA of primary header */
    st_qword(buf + GPTH_PtOfs, top_bpt);     /* LBA of this table */
    st_dword(buf + GPTH_Bcc, 0);
    for (i = 0, bcc = 0xFFFFFFFF; i < 92; bcc = crc32(bcc, buf[i++]))
      ;                             /* Calculate header check sum */
    st_dword(buf + GPTH_Bcc, ~bcc); /* Header check sum */
    if (disk_write(drv, buf, sz_drv - 1, 1) != RES_OK) return FR_DISK_ERR;

    /* Create protective MBR */
    memset(buf, 0, ss);
    memcpy(buf + MBR_Table, gpt_mbr, 16); /* Create a GPT partition */
    st_word(buf + BS_55AA, 0xAA55);
    if (disk_write(drv, buf, 0, 1) != RES_OK) return FR_DISK_ERR;

  } else
#  endif
  { /* Create partitions in MBR format */
    sz_drv32 = (u32)sz_drv;
    n_sc = N_SEC_TRACK; /* Determine drive CHS without any consideration of the drive geometry */
    for (n_hd = 8; n_hd != 0 && sz_drv32 / n_hd / n_sc > 1024; n_hd *= 2)
      ;
    if (n_hd == 0) n_hd = 255; /* Number of heads needs to be <256 */

    memset(buf, 0, FF_MAX_SS); /* Clear MBR */
    pte = buf + MBR_Table;     /* Partition table in the MBR */
    for (i = 0, nxt_alloc32  = n_sc; i < 4 && nxt_alloc32 != 0 && nxt_alloc32 < sz_drv32;
         i++, nxt_alloc32   += sz_part32) {
      sz_part32 = (u32)plst[i]; /* Get partition size */
      if (sz_part32 <= 100)
        sz_part32 =
            (sz_part32 == 100) ? sz_drv32 : sz_drv32 / 100 * sz_part32; /* Size in percentage? */
      if (nxt_alloc32 + sz_part32 > sz_drv32 || nxt_alloc32 + sz_part32 < nxt_alloc32)
        sz_part32 = sz_drv32 - nxt_alloc32; /* Clip at drive size */
      if (sz_part32 == 0) break;            /* End of table or no sector to allocate? */

      st_dword(pte + PTE_StLba, nxt_alloc32); /* Start LBA */
      st_dword(pte + PTE_SizLba, sz_part32);  /* Number of sectors */
      pte[PTE_System] = sys;                  /* System type */

      cy              = (uint)(nxt_alloc32 / n_sc / n_hd); /* Start cylinder */
      hd              = (byte)(nxt_alloc32 / n_sc % n_hd); /* Start head */
      sc              = (byte)(nxt_alloc32 % n_sc + 1);    /* Start sector */
      pte[PTE_StHead] = hd;
      pte[PTE_StSec]  = (byte)((cy >> 2 & 0xC0) | sc);
      pte[PTE_StCyl]  = (byte)cy;

      cy              = (uint)((nxt_alloc32 + sz_part32 - 1) / n_sc / n_hd); /* End cylinder */
      hd              = (byte)((nxt_alloc32 + sz_part32 - 1) / n_sc % n_hd); /* End head */
      sc              = (byte)((nxt_alloc32 + sz_part32 - 1) % n_sc + 1);    /* End sector */
      pte[PTE_EdHead] = hd;
      pte[PTE_EdSec]  = (byte)((cy >> 2 & 0xC0) | sc);
      pte[PTE_EdCyl]  = (byte)cy;

      pte += SZ_PTE; /* Next entry */
    }

    st_word(buf + BS_55AA, 0xAA55);                               /* MBR signature */
    if (disk_write(drv, buf, 0, 1) != RES_OK) return FR_DISK_ERR; /* Write it to the MBR */
  }

  return FR_OK;
}

FRESULT f_mkfs(const TCHAR     *path, /* Logical drive number */
               const MKFS_PARM *opt,  /* Format options */
               void *work, /* Pointer to working buffer (null: use len bytes of heap memory) */
               uint  len   /* Size of working buffer [byte] */
) {
  static const u16       cst[]   = {1,   4,   16, 64,
                                    256, 512, 0}; /* Cluster size boundary for FAT volume (4Ks unit) */
  static const u16       cst32[] = {1,  2,  4, 8,
                                    16, 32, 0}; /* Cluster size boundary for FAT32 volume (128Ks unit) */
  static const MKFS_PARM defopt  = {FM_ANY, 0, 0, 0, 0}; /* Default parameter */
  byte                   fsopt, fsty, sys, pdrv, ipart;
  byte                  *buf;
  byte                  *pte;
  u16                    ss; /* Sector size */
  u32                    sz_buf, sz_blk, n_clst, pau, nsect, n, vsn;
  LBA_t   sz_vol, b_vol, b_fat, b_data; /* Size of volume, Base LBA of volume, fat, data */
  LBA_t   sect, lba[2];
  u32     sz_rsv, sz_fat, sz_dir, sz_au; /* Size of reserved, fat, dir, data, cluster */
  uint    n_fat, n_root, i;              /* Index, Number of FATs and Number of roor dir entries */
  int     vol;
  DSTATUS ds;
  FRESULT res;

  /* Check mounted drive and clear work area */
  vol = get_ldnumber(&path); /* Get target logical drive */
  if (vol < 0) return FR_INVALID_DRIVE;
  if (FatFs[vol]) FatFs[vol]->fs_type = 0; /* Clear the fs object if mounted */
  pdrv  = LD2PD(vol);                      /* Hosting physical drive */
  ipart = LD2PT(vol); /* Hosting partition (0:create as new, 1..:existing partition) */

  /* Initialize the hosting physical drive */
  ds = disk_initialize(pdrv);
  if (ds & STA_NOINIT) return FR_NOT_READY;
  if (ds & STA_PROTECT) return FR_WRITE_PROTECTED;

  /* Get physical drive parameters (sz_drv, sz_blk and ss) */
  if (!opt) opt = &defopt; /* Use default parameter if it is not given */
  sz_blk = opt->align;
  if (sz_blk == 0)
    disk_ioctl(pdrv, GET_BLOCK_SIZE, &sz_blk); /* Block size from the paramter or lower layer */
  if (sz_blk == 0 || sz_blk > 0x8000 || (sz_blk & (sz_blk - 1)))
    sz_blk = 1; /* Use default if the block size is invalid */
#  if FF_MAX_SS != FF_MIN_SS
  if (disk_ioctl(pdrv, GET_SECTOR_SIZE, &ss) != RES_OK) return FR_DISK_ERR;
  if (ss > FF_MAX_SS || ss < FF_MIN_SS || (ss & (ss - 1))) return FR_DISK_ERR;
#  else
  ss = FF_MAX_SS;
#  endif

  /* Options for FAT sub-type and FAT parameters */
  fsopt  = opt->fmt & (FM_ANY | FM_SFD);
  n_fat  = (opt->n_fat >= 1 && opt->n_fat <= 2) ? opt->n_fat : 1;
  n_root = (opt->n_root >= 1 && opt->n_root <= 32768 && (opt->n_root % (ss / SZDIRE)) == 0)
               ? opt->n_root
               : 512;
  sz_au =
      (opt->au_size <= 0x1000000 && (opt->au_size & (opt->au_size - 1)) == 0) ? opt->au_size : 0;
  sz_au /= ss; /* Byte --> Sector */

  /* Get working buffer */
  sz_buf = len / ss; /* Size of working buffer [sector] */
  if (sz_buf == 0) return FR_NOT_ENOUGH_CORE;
  buf = (byte *)work; /* Working buffer */
#  if FF_USE_LFN == 3
  if (!buf) buf = ff_memalloc(sz_buf * ss); /* Use heap memory for working buffer */
#  endif
  if (!buf) return FR_NOT_ENOUGH_CORE;

  /* Determine where the volume to be located (b_vol, sz_vol) */
  b_vol = sz_vol = 0;
  if (FF_MULTI_PARTITION &&
      ipart != 0) { /* Is the volume associated with any specific partition? */
    /* Get partition location from the existing partition table */
    if (disk_read(pdrv, buf, 0, 1) != RES_OK) LEAVE_MKFS(FR_DISK_ERR); /* Load MBR */
    if (ld_word(buf + BS_55AA) != 0xAA55) LEAVE_MKFS(FR_MKFS_ABORTED); /* Check if MBR is valid */
#  if FF_LBA64
    if (buf[MBR_Table + PTE_System] == 0xEE) { /* GPT protective MBR? */
      u32 n_ent, ofs;
      u64 pt_lba;

      /* Get the partition location from GPT */
      if (disk_read(pdrv, buf, 1, 1) != RES_OK)
        LEAVE_MKFS(FR_DISK_ERR); /* Load GPT header sector (next to MBR) */
      if (!test_gpt_header(buf)) LEAVE_MKFS(FR_MKFS_ABORTED); /* Check if GPT header is valid */
      n_ent  = ld_dword(buf + GPTH_PtNum);                    /* Number of entries */
      pt_lba = ld_qword(buf + GPTH_PtOfs);                    /* Table start sector */
      ofs = i = 0;
      while (n_ent) { /* Find MS Basic partition with order of ipart */
        if (ofs == 0 && disk_read(pdrv, buf, pt_lba++, 1) != RES_OK)
          LEAVE_MKFS(FR_DISK_ERR); /* Get PT sector */
        if (!memcmp(buf + ofs + GPTE_PtGuid, GUID_MS_Basic, 16) &&
            ++i == ipart) { /* MS basic data partition? */
          b_vol  = ld_qword(buf + ofs + GPTE_FstLba);
          sz_vol = ld_qword(buf + ofs + GPTE_LstLba) - b_vol + 1;
          break;
        }
        n_ent--;
        ofs = (ofs + SZ_GPTE) % ss; /* Next entry */
      }
      if (n_ent == 0) LEAVE_MKFS(FR_MKFS_ABORTED); /* Partition not found */
      fsopt |= 0x80;                               /* Partitioning is in GPT */
    } else
#  endif
    { /* Get the partition location from MBR partition table */
      pte = buf + (MBR_Table + (ipart - 1) * SZ_PTE);
      if (ipart > 4 || pte[PTE_System] == 0) LEAVE_MKFS(FR_MKFS_ABORTED); /* No partition? */
      b_vol  = ld_dword(pte + PTE_StLba);  /* Get volume start sector */
      sz_vol = ld_dword(pte + PTE_SizLba); /* Get volume size */
    }
  } else { /* The volume is associated with a physical drive */
    if (disk_ioctl(pdrv, GET_SECTOR_COUNT, &sz_vol) != RES_OK) LEAVE_MKFS(FR_DISK_ERR);
    if (!(fsopt & FM_SFD)) { /* To be partitioned? */
                             /* Create a single-partition on the drive in this function */
#  if FF_LBA64
      if (sz_vol >= FF_MIN_GPT) { /* Which partition type to create, MBR or GPT? */
        fsopt  |= 0x80;           /* Partitioning is in GPT */
        b_vol   = GPT_ALIGN / ss;
        sz_vol -= b_vol + GPT_ITEMS * SZ_GPTE / ss + 1; /* Estimated partition offset and size */
      } else
#  endif
      { /* Partitioning is in MBR */
        if (sz_vol > N_SEC_TRACK) {
          b_vol   = N_SEC_TRACK;
          sz_vol -= b_vol; /* Estimated partition offset and size */
        }
      }
    }
  }
  if (sz_vol < 128) LEAVE_MKFS(FR_MKFS_ABORTED); /* Check if volume size is >=128s */

  /* Now start to create an FAT volume at b_vol and sz_vol */

  do {                                       /* Pre-determine the FAT type */
    if (FF_FS_EXFAT && (fsopt & FM_EXFAT)) { /* exFAT possible? */
      if ((fsopt & FM_ANY) == FM_EXFAT || sz_vol >= 0x4000000 ||
          sz_au > 128) { /* exFAT only, vol >= 64MS or sz_au > 128S ? */
        fsty = FS_EXFAT;
        break;
      }
    }
#  if FF_LBA64
    if (sz_vol >= 0x100000000) LEAVE_MKFS(FR_MKFS_ABORTED); /* Too large volume for FAT/FAT32 */
#  endif
    if (sz_au > 128) sz_au = 128; /* Invalid AU for FAT/FAT32? */
    if (fsopt & FM_FAT32) {       /* FAT32 possible? */
      if (!(fsopt & FM_FAT)) {    /* no-FAT? */
        fsty = FS_FAT32;
        break;
      }
    }
    if (!(fsopt & FM_FAT)) LEAVE_MKFS(FR_INVALID_PARAMETER); /* no-FAT? */
    fsty = FS_FAT16;
  } while (0);

  vsn = (u32)sz_vol + GET_FATTIME(); /* VSN generated from current time and partitiion size */

#  if FF_FS_EXFAT
  if (fsty == FS_EXFAT) { /* Create an exFAT volume */
    u32      szb_bit, szb_case, sum, nbit, clu, clen[3];
    char16_t ch, si;
    uint     j, st;

    if (sz_vol < 0x1000) LEAVE_MKFS(FR_MKFS_ABORTED); /* Too small volume for exFAT? */
#    if FF_USE_TRIM
    lba[0] = b_vol;
    lba[1] = b_vol + sz_vol - 1; /* Inform storage device that the volume area may be erased */
    disk_ioctl(pdrv, CTRL_TRIM, lba);
#    endif
    /* Determine FAT location, data location and number of clusters */
    if (sz_au == 0) { /* AU auto-selection */
      sz_au = 8;
      if (sz_vol >= 0x80000) sz_au = 64;    /* >= 512Ks */
      if (sz_vol >= 0x4000000) sz_au = 256; /* >= 64Ms */
    }
    b_fat  = b_vol + 32;                                    /* FAT start at offset 32 */
    sz_fat = (u32)((sz_vol / sz_au + 2) * 4 + ss - 1) / ss; /* Number of FAT sectors */
    b_data = (b_fat + sz_fat + sz_blk - 1) &
             ~((LBA_t)sz_blk - 1); /* Align data area to the erase block boundary */
    if (b_data - b_vol >= sz_vol / 2) LEAVE_MKFS(FR_MKFS_ABORTED); /* Too small volume? */
    n_clst = (u32)((sz_vol - (b_data - b_vol)) / sz_au);           /* Number of clusters */
    if (n_clst < 16) LEAVE_MKFS(FR_MKFS_ABORTED);                  /* Too few clusters? */
    if (n_clst > MAX_EXFAT) LEAVE_MKFS(FR_MKFS_ABORTED);           /* Too many clusters? */

    szb_bit = (n_clst + 7) / 8;                          /* Size of allocation bitmap */
    clen[0] = (szb_bit + sz_au * ss - 1) / (sz_au * ss); /* Number of allocation bitmap clusters */

    /* Create a compressed up-case table */
    sect     = b_data + sz_au * clen[0]; /* Table start sector */
    sum      = 0;                        /* Table checksum to be stored in the 82 entry */
    st       = 0;
    si       = 0;
    i        = 0;
    j        = 0;
    szb_case = 0;
    do {
      switch (st) {
      case 0:
        ch = (char16_t)ff_wtoupper(si); /* Get an up-case char */
        if (ch != si) {
          si++;
          break; /* Store the up-case char if exist */
        }
        for (j = 1; (char16_t)(si + j) && (char16_t)(si + j) == ff_wtoupper((char16_t)(si + j));
             j++)
          ; /* Get run length of no-case block */
        if (j >= 128) {
          ch = 0xFFFF;
          st = 2;
          break; /* Compress the no-case block if run is >= 128 chars */
        }
        st = 1; /* Do not compress short run */
                /* FALLTHROUGH */
      case 1:
        ch = si++; /* Fill the short run */
        if (--j == 0) st = 0;
        break;

      default:
        ch  = (char16_t)j;
        si += (char16_t)j; /* Number of chars to skip */
        st  = 0;
      }
      sum       = xsum32(buf[i + 0] = (byte)ch, sum); /* Put it into the write buffer */
      sum       = xsum32(buf[i + 1] = (byte)(ch >> 8), sum);
      i        += 2;
      szb_case += 2;
      if (si == 0 ||
          i == sz_buf * ss) { /* Write buffered data when buffer full or end of process */
        n = (i + ss - 1) / ss;
        if (disk_write(pdrv, buf, sect, n) != RES_OK) LEAVE_MKFS(FR_DISK_ERR);
        sect += n;
        i     = 0;
      }
    } while (si);
    clen[1] = (szb_case + sz_au * ss - 1) / (sz_au * ss); /* Number of up-case table clusters */
    clen[2] = 1;                                          /* Number of root dir clusters */

    /* Initialize the allocation bitmap */
    sect  = b_data;
    nsect = (szb_bit + ss - 1) / ss; /* Start of bitmap and number of bitmap sectors */
    nbit  = clen[0] + clen[1] +
           clen[2]; /* Number of clusters in-use by system (bitmap, up-case and root-dir) */
    do {
      memset(buf, 0, sz_buf * ss); /* Initialize bitmap buffer */
      for (i = 0; nbit != 0 && i / 8 < sz_buf * ss; buf[i / 8] |= 1 << (i % 8), i++, nbit--)
        ;                                    /* Mark used clusters */
      n = (nsect > sz_buf) ? sz_buf : nsect; /* Write the buffered data */
      if (disk_write(pdrv, buf, sect, n) != RES_OK) LEAVE_MKFS(FR_DISK_ERR);
      sect  += n;
      nsect -= n;
    } while (nsect);

    /* Initialize the FAT */
    sect  = b_fat;
    nsect = sz_fat; /* Start of FAT and number of FAT sectors */
    j = nbit = clu = 0;
    do {
      memset(buf, 0, sz_buf * ss);
      i = 0;          /* Clear work area and reset write offset */
      if (clu == 0) { /* Initialize FAT [0] and FAT[1] */
        st_dword(buf + i, 0xFFFFFFF8);
        i += 4;
        clu++;
        st_dword(buf + i, 0xFFFFFFFF);
        i += 4;
        clu++;
      }
      do {                                     /* Create chains of bitmap, up-case and root dir */
        while (nbit != 0 && i < sz_buf * ss) { /* Create a chain */
          st_dword(buf + i, (nbit > 1) ? clu + 1 : 0xFFFFFFFF);
          i += 4;
          clu++;
          nbit--;
        }
        if (nbit == 0 && j < 3) nbit = clen[j++]; /* Get next chain length */
      } while (nbit != 0 && i < sz_buf * ss);
      n = (nsect > sz_buf) ? sz_buf : nsect; /* Write the buffered data */
      if (disk_write(pdrv, buf, sect, n) != RES_OK) LEAVE_MKFS(FR_DISK_ERR);
      sect  += n;
      nsect -= n;
    } while (nsect);

    /* Initialize the root directory */
    memset(buf, 0, sz_buf * ss);
    buf[SZDIRE * 0 + 0] = ET_VLABEL;              /* Volume label entry (no label) */
    buf[SZDIRE * 1 + 0] = ET_BITMAP;              /* Bitmap entry */
    st_dword(buf + SZDIRE * 1 + 20, 2);           /*  cluster */
    st_dword(buf + SZDIRE * 1 + 24, szb_bit);     /*  size */
    buf[SZDIRE * 2 + 0] = ET_UPCASE;              /* Up-case table entry */
    st_dword(buf + SZDIRE * 2 + 4, sum);          /*  sum */
    st_dword(buf + SZDIRE * 2 + 20, 2 + clen[0]); /*  cluster */
    st_dword(buf + SZDIRE * 2 + 24, szb_case);    /*  size */
    sect  = b_data + sz_au * (clen[0] + clen[1]);
    nsect = sz_au; /* Start of the root directory and number of sectors */
    do {           /* Fill root directory sectors */
      n = (nsect > sz_buf) ? sz_buf : nsect;
      if (disk_write(pdrv, buf, sect, n) != RES_OK) LEAVE_MKFS(FR_DISK_ERR);
      memset(buf, 0, ss); /* Rest of entries are filled with zero */
      sect  += n;
      nsect -= n;
    } while (nsect);

    /* Create two set of the exFAT VBR blocks */
    sect = b_vol;
    for (n = 0; n < 2; n++) {
      /* Main record (+0) */
      memset(buf, 0, ss);
      memcpy(buf + BS_JmpBoot,
             "\xEB\x76\x90"
             "EXFAT   ",
             11);                           /* Boot jump code (x86), OEM name */
      st_qword(buf + BPB_VolOfsEx, b_vol);  /* Volume offset in the physical drive [sector] */
      st_qword(buf + BPB_TotSecEx, sz_vol); /* Volume size [sector] */
      st_dword(buf + BPB_FatOfsEx, (u32)(b_fat - b_vol));    /* FAT offset [sector] */
      st_dword(buf + BPB_FatSzEx, sz_fat);                   /* FAT size [sector] */
      st_dword(buf + BPB_DataOfsEx, (u32)(b_data - b_vol));  /* Data offset [sector] */
      st_dword(buf + BPB_NumClusEx, n_clst);                 /* Number of clusters */
      st_dword(buf + BPB_RootClusEx, 2 + clen[0] + clen[1]); /* Root dir cluster # */
      st_dword(buf + BPB_VolIDEx, vsn);                      /* VSN */
      st_word(buf + BPB_FSVerEx, 0x100);                     /* Filesystem version (1.00) */
      for (buf[BPB_BytsPerSecEx] = 0, i = ss; i >>= 1; buf[BPB_BytsPerSecEx]++)
        ; /* Log2 of sector size [byte] */
      for (buf[BPB_SecPerClusEx] = 0, i = sz_au; i >>= 1; buf[BPB_SecPerClusEx]++)
        ;                                   /* Log2 of cluster size [sector] */
      buf[BPB_NumFATsEx] = 1;               /* Number of FATs */
      buf[BPB_DrvNumEx]  = 0x80;            /* Drive number (for int13) */
      st_word(buf + BS_BootCodeEx, 0xFEEB); /* Boot code (x86) */
      st_word(buf + BS_55AA, 0xAA55);       /* Signature (placed here regardless of sector size) */
      for (i = sum = 0; i < ss; i++) {      /* VBR checksum */
        if (i != BPB_VolFlagEx && i != BPB_VolFlagEx + 1 && i != BPB_PercInUseEx)
          sum = xsum32(buf[i], sum);
      }
      if (disk_write(pdrv, buf, sect++, 1) != RES_OK) LEAVE_MKFS(FR_DISK_ERR);
      /* Extended bootstrap record (+1..+8) */
      memset(buf, 0, ss);
      st_word(buf + ss - 2, 0xAA55); /* Signature (placed at end of sector) */
      for (j = 1; j < 9; j++) {
        for (i = 0; i < ss; sum = xsum32(buf[i++], sum))
          ; /* VBR checksum */
        if (disk_write(pdrv, buf, sect++, 1) != RES_OK) LEAVE_MKFS(FR_DISK_ERR);
      }
      /* OEM/Reserved record (+9..+10) */
      memset(buf, 0, ss);
      for (; j < 11; j++) {
        for (i = 0; i < ss; sum = xsum32(buf[i++], sum))
          ; /* VBR checksum */
        if (disk_write(pdrv, buf, sect++, 1) != RES_OK) LEAVE_MKFS(FR_DISK_ERR);
      }
      /* Sum record (+11) */
      for (i = 0; i < ss; i += 4)
        st_dword(buf + i, sum); /* Fill with checksum value */
      if (disk_write(pdrv, buf, sect++, 1) != RES_OK) LEAVE_MKFS(FR_DISK_ERR);
    }

  } else
#  endif /* FF_FS_EXFAT */
  {      /* Create an FAT/FAT32 volume */
    do {
      pau = sz_au;
      /* Pre-determine number of clusters and FAT sub-type */
      if (fsty == FS_FAT32) {        /* FAT32 volume */
        if (pau == 0) {              /* AU auto-selection */
          n = (u32)sz_vol / 0x20000; /* Volume size in unit of 128KS */
          for (i = 0, pau = 1; cst32[i] && cst32[i] <= n; i++, pau <<= 1)
            ; /* Get from table */
        }
        n_clst = (u32)sz_vol / pau;              /* Number of clusters */
        sz_fat = (n_clst * 4 + 8 + ss - 1) / ss; /* FAT size [sector] */
        sz_rsv = 32;                             /* Number of reserved sectors */
        sz_dir = 0;                              /* No static directory */
        if (n_clst <= MAX_FAT16 || n_clst > MAX_FAT32) LEAVE_MKFS(FR_MKFS_ABORTED);
      } else {                      /* FAT volume */
        if (pau == 0) {             /* au auto-selection */
          n = (u32)sz_vol / 0x1000; /* Volume size in unit of 4KS */
          for (i = 0, pau = 1; cst[i] && cst[i] <= n; i++, pau <<= 1)
            ; /* Get from table */
        }
        n_clst = (u32)sz_vol / pau;
        if (n_clst > MAX_FAT12) {
          n = n_clst * 2 + 4; /* FAT size [byte] */
        } else {
          fsty = FS_FAT12;
          n    = (n_clst * 3 + 1) / 2 + 3; /* FAT size [byte] */
        }
        sz_fat = (n + ss - 1) / ss;         /* FAT size [sector] */
        sz_rsv = 1;                         /* Number of reserved sectors */
        sz_dir = (u32)n_root * SZDIRE / ss; /* Root dir size [sector] */
      }
      b_fat  = b_vol + sz_rsv;                  /* FAT base */
      b_data = b_fat + sz_fat * n_fat + sz_dir; /* Data base */

      /* Align data area to erase block boundary (for flash memory media) */
      n = (u32)(((b_data + sz_blk - 1) & ~(sz_blk - 1)) -
                b_data);      /* Sectors to next nearest from current data base */
      if (fsty == FS_FAT32) { /* FAT32: Move FAT */
        sz_rsv += n;
        b_fat  += n;
      } else {           /* FAT: Expand FAT */
        if (n % n_fat) { /* Adjust fractional error if needed */
          n--;
          sz_rsv++;
          b_fat++;
        }
        sz_fat += n / n_fat;
      }

      /* Determine number of clusters and final check of validity of the FAT sub-type */
      if (sz_vol < b_data + pau * 16 - b_vol) LEAVE_MKFS(FR_MKFS_ABORTED); /* Too small volume? */
      n_clst = ((u32)sz_vol - sz_rsv - sz_fat * n_fat - sz_dir) / pau;
      if (fsty == FS_FAT32) {
        if (n_clst <= MAX_FAT16) {                            /* Too few clusters for FAT32? */
          if (sz_au == 0 && (sz_au = pau / 2) != 0) continue; /* Adjust cluster size and retry */
          LEAVE_MKFS(FR_MKFS_ABORTED);
        }
      }
      if (fsty == FS_FAT16) {
        if (n_clst > MAX_FAT16) { /* Too many clusters for FAT16 */
          if (sz_au == 0 && (pau * 2) <= 64) {
            sz_au = pau * 2;
            continue; /* Adjust cluster size and retry */
          }
          if ((fsopt & FM_FAT32)) {
            fsty = FS_FAT32;
            continue; /* Switch type to FAT32 and retry */
          }
          if (sz_au == 0 && (sz_au = pau * 2) <= 128) continue; /* Adjust cluster size and retry */
          LEAVE_MKFS(FR_MKFS_ABORTED);
        }
        if (n_clst <= MAX_FAT12) {                              /* Too few clusters for FAT16 */
          if (sz_au == 0 && (sz_au = pau * 2) <= 128) continue; /* Adjust cluster size and retry */
          LEAVE_MKFS(FR_MKFS_ABORTED);
        }
      }
      if (fsty == FS_FAT12 && n_clst > MAX_FAT12)
        LEAVE_MKFS(FR_MKFS_ABORTED); /* Too many clusters for FAT12 */

      /* Ok, it is the valid cluster configuration */
      break;
    } while (1);

#  if FF_USE_TRIM
    lba[0] = b_vol;
    lba[1] = b_vol + sz_vol - 1; /* Inform storage device that the volume area may be erased */
    disk_ioctl(pdrv, CTRL_TRIM, lba);
#  endif
    /* Create FAT VBR */
    memset(buf, 0, ss);
    memcpy(buf + BS_JmpBoot,
           "\xEB\xFE\x90"
           "MSDOS5.0",
           11);                                 /* Boot jump code (x86), OEM name */
    st_word(buf + BPB_BytsPerSec, ss);          /* Sector size [byte] */
    buf[BPB_SecPerClus] = (byte)pau;            /* Cluster size [sector] */
    st_word(buf + BPB_RsvdSecCnt, (u16)sz_rsv); /* Size of reserved area */
    buf[BPB_NumFATs] = (byte)n_fat;             /* Number of FATs */
    st_word(buf + BPB_RootEntCnt,
            (u16)((fsty == FS_FAT32) ? 0 : n_root)); /* Number of root directory entries */
    if (sz_vol < 0x10000) {
      st_word(buf + BPB_TotSec16, (u16)sz_vol); /* Volume size in 16-bit LBA */
    } else {
      st_dword(buf + BPB_TotSec32, (u32)sz_vol); /* Volume size in 32-bit LBA */
    }
    buf[BPB_Media] = 0xF8;                   /* Media descriptor byte */
    st_word(buf + BPB_SecPerTrk, 63);        /* Number of sectors per track (for int13) */
    st_word(buf + BPB_NumHeads, 255);        /* Number of heads (for int13) */
    st_dword(buf + BPB_HiddSec, (u32)b_vol); /* Volume offset in the physical drive [sector] */
    if (fsty == FS_FAT32) {
      st_dword(buf + BS_VolID32, vsn);     /* VSN */
      st_dword(buf + BPB_FATSz32, sz_fat); /* FAT size [sector] */
      st_dword(buf + BPB_RootClus32, 2);   /* Root directory cluster # (2) */
      st_word(buf + BPB_FSInfo32, 1);      /* Offset of FSINFO sector (VBR + 1) */
      st_word(buf + BPB_BkBootSec32, 6);   /* Offset of backup VBR (VBR + 6) */
      buf[BS_DrvNum32]  = 0x80;            /* Drive number (for int13) */
      buf[BS_BootSig32] = 0x29;            /* Extended boot signature */
      memcpy(buf + BS_VolLab32,
             "NO NAME    "
             "FAT32   ",
             19); /* Volume label, FAT signature */
    } else {
      st_dword(buf + BS_VolID, vsn);           /* VSN */
      st_word(buf + BPB_FATSz16, (u16)sz_fat); /* FAT size [sector] */
      buf[BS_DrvNum]  = 0x80;                  /* Drive number (for int13) */
      buf[BS_BootSig] = 0x29;                  /* Extended boot signature */
      memcpy(buf + BS_VolLab,
             "NO NAME    "
             "FAT     ",
             19); /* Volume label, FAT signature */
    }
    st_word(buf + BS_55AA, 0xAA55); /* Signature (offset is fixed here regardless of sector size) */
    if (disk_write(pdrv, buf, b_vol, 1) != RES_OK)
      LEAVE_MKFS(FR_DISK_ERR); /* Write it to the VBR sector */

    /* Create FSINFO record if needed */
    if (fsty == FS_FAT32) {
      disk_write(pdrv, buf, b_vol + 6, 1); /* Write backup VBR (VBR + 6) */
      memset(buf, 0, ss);
      st_dword(buf + FSI_LeadSig, 0x41615252);
      st_dword(buf + FSI_StrucSig, 0x61417272);
      st_dword(buf + FSI_Free_Count, n_clst - 1); /* Number of free clusters */
      st_dword(buf + FSI_Nxt_Free, 2);            /* Last allocated cluster# */
      st_word(buf + BS_55AA, 0xAA55);
      disk_write(pdrv, buf, b_vol + 7, 1); /* Write backup FSINFO (VBR + 7) */
      disk_write(pdrv, buf, b_vol + 1, 1); /* Write original FSINFO (VBR + 1) */
    }

    /* Initialize FAT area */
    memset(buf, 0, sz_buf * ss);
    sect = b_fat;                 /* FAT start sector */
    for (i = 0; i < n_fat; i++) { /* Initialize FATs each */
      if (fsty == FS_FAT32) {
        st_dword(buf + 0, 0xFFFFFFF8); /* FAT[0] */
        st_dword(buf + 4, 0xFFFFFFFF); /* FAT[1] */
        st_dword(buf + 8, 0x0FFFFFFF); /* FAT[2] (root directory) */
      } else {
        st_dword(buf + 0, (fsty == FS_FAT12) ? 0xFFFFF8 : 0xFFFFFFF8); /* FAT[0] and FAT[1] */
      }
      nsect = sz_fat; /* Number of FAT sectors */
      do {            /* Fill FAT sectors */
        n = (nsect > sz_buf) ? sz_buf : nsect;
        if (disk_write(pdrv, buf, sect, (uint)n) != RES_OK) LEAVE_MKFS(FR_DISK_ERR);
        memset(buf, 0, ss); /* Rest of FAT all are cleared */
        sect  += n;
        nsect -= n;
      } while (nsect);
    }

    /* Initialize root directory (fill with zero) */
    nsect = (fsty == FS_FAT32) ? pau : sz_dir; /* Number of root directory sectors */
    do {
      n = (nsect > sz_buf) ? sz_buf : nsect;
      if (disk_write(pdrv, buf, sect, (uint)n) != RES_OK) LEAVE_MKFS(FR_DISK_ERR);
      sect  += n;
      nsect -= n;
    } while (nsect);
  }

  /* A FAT volume has been created here */

  /* Determine system ID in the MBR partition table */
  if (FF_FS_EXFAT && fsty == FS_EXFAT) {
    sys = 0x07; /* exFAT */
  } else if (fsty == FS_FAT32) {
    sys = 0x0C; /* FAT32X */
  } else if (sz_vol >= 0x10000) {
    sys = 0x06; /* FAT12/16 (large) */
  } else if (fsty == FS_FAT16) {
    sys = 0x04; /* FAT16 */
  } else {
    sys = 0x01; /* FAT12 */
  }

  /* Update partition information */
  if (FF_MULTI_PARTITION && ipart != 0) { /* Volume is in the existing partition */
    if (!FF_LBA64 || !(fsopt & 0x80)) {   /* Is the partition in MBR? */
      /* Update system ID in the partition table */
      if (disk_read(pdrv, buf, 0, 1) != RES_OK) LEAVE_MKFS(FR_DISK_ERR); /* Read the MBR */
      buf[MBR_Table + (ipart - 1) * SZ_PTE + PTE_System] = sys;          /* Set system ID */
      if (disk_write(pdrv, buf, 0, 1) != RES_OK)
        LEAVE_MKFS(FR_DISK_ERR); /* Write it back to the MBR */
    }
  } else {                   /* Volume as a new single partition */
    if (!(fsopt & FM_SFD)) { /* Create partition table if not in SFD format */
      lba[0] = sz_vol;
      lba[1] = 0;
      res    = create_partition(pdrv, lba, sys, buf);
      if (res != FR_OK) LEAVE_MKFS(res);
    }
  }

  if (disk_ioctl(pdrv, CTRL_SYNC, 0) != RES_OK) LEAVE_MKFS(FR_DISK_ERR);

  LEAVE_MKFS(FR_OK);
}

#  if FF_MULTI_PARTITION
/*-----------------------------------------------------------------------*/
/* Create Partition Table on the Physical Drive                          */
/*-----------------------------------------------------------------------*/

FRESULT f_fdisk(byte        pdrv,   /* Physical drive number */
                const LBA_t ptbl[], /* Pointer to the size table for each partitions */
                void       *work    /* Pointer to the working buffer (null: use heap memory) */
) {
  byte   *buf = (byte *)work;
  DSTATUS stat;
  FRESULT res;

  /* Initialize the physical drive */
  stat = disk_initialize(pdrv);
  if (stat & STA_NOINIT) return FR_NOT_READY;
  if (stat & STA_PROTECT) return FR_WRITE_PROTECTED;

#    if FF_USE_LFN == 3
  if (!buf) buf = ff_memalloc(FF_MAX_SS); /* Use heap memory for working buffer */
#    endif
  if (!buf) return FR_NOT_ENOUGH_CORE;

  res = create_partition(
      pdrv, ptbl, 0x07,
      buf); /* Create partitions (system ID is temporary setting and determined by f_mkfs) */

  LEAVE_MKFS(res);
}

#  endif /* FF_MULTI_PARTITION */
#endif   /* !FF_FS_READONLY && FF_USE_MKFS */

#if FF_USE_STRFUNC
#  if FF_USE_LFN && FF_LFN_UNICODE && (FF_STRF_ENCODE < 0 || FF_STRF_ENCODE > 3)
#    error Wrong FF_STRF_ENCODE setting
#  endif
/*-----------------------------------------------------------------------*/
/* Get a String from the File                                            */
/*-----------------------------------------------------------------------*/

TCHAR *f_gets(TCHAR *buff, /* Pointer to the buffer to store read string */
              int    len,  /* Size of string buffer (items) */
              FIL   *fp    /* Pointer to the file object */
) {
  int    nc = 0;
  TCHAR *p  = buff;
  byte   s[4];
  uint   rc;
  u32    dc;
#  if FF_USE_LFN && FF_LFN_UNICODE && FF_STRF_ENCODE <= 2
  char16_t wc;
#  endif
#  if FF_USE_LFN && FF_LFN_UNICODE && FF_STRF_ENCODE == 3
  uint ct;
#  endif

#  if FF_USE_LFN && FF_LFN_UNICODE /* With code conversion (Unicode API) */
  /* Make a room for the character and terminator  */
  if (FF_LFN_UNICODE == 1) len -= (FF_STRF_ENCODE == 0) ? 1 : 2;
  if (FF_LFN_UNICODE == 2) len -= (FF_STRF_ENCODE == 0) ? 3 : 4;
  if (FF_LFN_UNICODE == 3) len -= 1;
  while (nc < len) {
#    if FF_STRF_ENCODE == 0 /* Read a character in ANSI/OEM */
    f_read(fp, s, 1, &rc);  /* Get a code unit */
    if (rc != 1) break;     /* EOF? */
    wc = s[0];
    if (dbc_1st((byte)wc)) {                   /* DBC 1st byte? */
      f_read(fp, s, 1, &rc);                   /* Get 2nd byte */
      if (rc != 1 || !dbc_2nd(s[0])) continue; /* Wrong code? */
      wc = wc << 8 | s[0];
    }
    dc = ff_oem2uni(wc, CODEPAGE);                   /* Convert ANSI/OEM into Unicode */
    if (dc == 0) continue;                           /* Conversion error? */
#    elif FF_STRF_ENCODE == 1 || FF_STRF_ENCODE == 2 /* Read a character in UTF-16LE/BE */
    f_read(fp, s, 2, &rc); /* Get a code unit */
    if (rc != 2) break;    /* EOF? */
    dc = (FF_STRF_ENCODE == 1) ? ld_word(s) : s[0] << 8 | s[1];
    if (IsSurrogateL(dc)) continue; /* Broken surrogate pair? */
    if (IsSurrogateH(dc)) {         /* High surrogate? */
      f_read(fp, s, 2, &rc);        /* Get low surrogate */
      if (rc != 2) break;           /* EOF? */
      wc = (FF_STRF_ENCODE == 1) ? ld_word(s) : s[0] << 8 | s[1];
      if (!IsSurrogateL(wc)) continue;                 /* Broken surrogate pair? */
      dc = ((dc & 0x3FF) + 0x40) << 10 | (wc & 0x3FF); /* Merge surrogate pair */
    }
#    else                                            /* Read a character in UTF-8 */
    f_read(fp, s, 1, &rc); /* Get a code unit */
    if (rc != 1) break;    /* EOF? */
    dc = s[0];
    if (dc >= 0x80) { /* Multi-byte sequence? */
      ct = 0;
      if ((dc & 0xE0) == 0xC0) { /* 2-byte sequence? */
        dc &= 0x1F;
        ct  = 1;
      }
      if ((dc & 0xF0) == 0xE0) { /* 3-byte sequence? */
        dc &= 0x0F;
        ct  = 2;
      }
      if ((dc & 0xF8) == 0xF0) { /* 4-byte sequence? */
        dc &= 0x07;
        ct  = 3;
      }
      if (ct == 0) continue;
      f_read(fp, s, ct, &rc); /* Get trailing bytes */
      if (rc != ct) break;
      rc = 0;
      do { /* Merge the byte sequence */
        if ((s[rc] & 0xC0) != 0x80) break;
        dc = dc << 6 | (s[rc] & 0x3F);
      } while (++rc < ct);
      if (rc != ct || dc < 0x80 || IsSurrogate(dc) || dc >= 0x110000)
        continue; /* Wrong encoding? */
    }
#    endif
    /* A code point is avaialble in dc to be output */

    if (FF_USE_STRFUNC == 2 && dc == '\r') continue; /* Strip \r off if needed */
#    if FF_LFN_UNICODE == 1 || FF_LFN_UNICODE == 3   /* Output it in UTF-16/32 encoding */
    if (FF_LFN_UNICODE == 1 && dc >= 0x10000) {      /* Out of BMP at UTF-16? */
      *p++ = (TCHAR)(0xD800 | ((dc >> 10) - 0x40));
      nc++;                       /* Make and output high surrogate */
      dc = 0xDC00 | (dc & 0x3FF); /* Make low surrogate */
    }
    *p++ = (TCHAR)dc;
    nc++;
    if (dc == '\n') break;    /* End of line? */
#    elif FF_LFN_UNICODE == 2 /* Output it in UTF-8 encoding */
    if (dc < 0x80) { /* Single byte? */
      *p++ = (TCHAR)dc;
      nc++;
      if (dc == '\n') break; /* End of line? */
    } else if (dc < 0x800) { /* 2-byte sequence? */
      *p++  = (TCHAR)(0xC0 | (dc >> 6 & 0x1F));
      *p++  = (TCHAR)(0x80 | (dc >> 0 & 0x3F));
      nc   += 2;
    } else if (dc < 0x10000) { /* 3-byte sequence? */
      *p++  = (TCHAR)(0xE0 | (dc >> 12 & 0x0F));
      *p++  = (TCHAR)(0x80 | (dc >> 6 & 0x3F));
      *p++  = (TCHAR)(0x80 | (dc >> 0 & 0x3F));
      nc   += 3;
    } else { /* 4-byte sequence */
      *p++  = (TCHAR)(0xF0 | (dc >> 18 & 0x07));
      *p++  = (TCHAR)(0x80 | (dc >> 12 & 0x3F));
      *p++  = (TCHAR)(0x80 | (dc >> 6 & 0x3F));
      *p++  = (TCHAR)(0x80 | (dc >> 0 & 0x3F));
      nc   += 4;
    }
#    endif
  }

#  else /* Byte-by-byte read without any conversion (ANSI/OEM API) */
  len -= 1; /* Make a room for the terminator */
  while (nc < len) {
    f_read(fp, s, 1, &rc); /* Get a byte */
    if (rc != 1) break;    /* EOF? */
    dc = s[0];
    if (FF_USE_STRFUNC == 2 && dc == '\r') continue;
    *p++ = (TCHAR)dc;
    nc++;
    if (dc == '\n') break;
  }
#  endif

  *p = 0;               /* Terminate the string */
  return nc ? buff : 0; /* When no data read due to EOF or error, return with error. */
}

#  if !FF_FS_READONLY
#    define SZ_PUTC_BUF 64
#    define SZ_NUM_BUF  32

/*-----------------------------------------------------------------------*/
/* Put a Character to the File (with sub-functions)                      */
/*-----------------------------------------------------------------------*/

/* Output buffer and work area */

typedef struct {
  FIL *fp;        /* Ptr to the writing file */
  int  idx, nchr; /* Write index of buf[] (-1:error), number of encoding units written */
#    if FF_USE_LFN && FF_LFN_UNICODE == 1
  char16_t hs;
#    elif FF_USE_LFN && FF_LFN_UNICODE == 2
  byte bs[4];
  uint wi, ct;
#    endif
  byte buf[SZ_PUTC_BUF]; /* Write buffer */
} putbuff;

/* Buffered file write with code conversion */

static void putc_bfd(putbuff *pb, TCHAR c) {
  uint n;
  int  i, nc;
#    if FF_USE_LFN && FF_LFN_UNICODE
  char16_t hs, wc;
#      if FF_LFN_UNICODE == 2
  u32          dc;
  const TCHAR *tp;
#      endif
#    endif

  if (FF_USE_STRFUNC == 2 && c == '\n') { /* LF -> CRLF conversion */
    putc_bfd(pb, '\r');
  }

  i = pb->idx;       /* Write index of pb->buf[] */
  if (i < 0) return; /* In write error? */
  nc = pb->nchr;     /* Write unit counter */

#    if FF_USE_LFN && FF_LFN_UNICODE
#      if FF_LFN_UNICODE == 1 /* UTF-16 input */
  if (IsSurrogateH(c)) {      /* Is this a high-surrogate? */
    pb->hs = c;
    return; /* Save it for next */
  }
  hs     = pb->hs;
  pb->hs = 0;
  if (hs != 0) {                  /* Is there a leading high-surrogate? */
    if (!IsSurrogateL(c)) hs = 0; /* Discard high-surrogate if not a surrogate pair */
  } else {
    if (IsSurrogateL(c)) return; /* Discard stray low-surrogate */
  }
  wc = c;
#      elif FF_LFN_UNICODE == 2 /* UTF-8 input */
  for (;;) {
    if (pb->ct == 0) {                          /* Out of multi-byte sequence? */
      pb->bs[pb->wi = 0] = (byte)c;             /* Save 1st byte */
      if ((byte)c < 0x80) break;                /* Single byte code? */
      if (((byte)c & 0xE0) == 0xC0) pb->ct = 1; /* 2-byte sequence? */
      if (((byte)c & 0xF0) == 0xE0) pb->ct = 2; /* 3-byte sequence? */
      if (((byte)c & 0xF8) == 0xF0) pb->ct = 3; /* 4-byte sequence? */
      return;                                   /* Wrong leading byte (discard it) */
    } else {                                    /* In the multi-byte sequence */
      if (((byte)c & 0xC0) != 0x80) {           /* Broken sequence? */
        pb->ct = 0;
        continue; /* Discard the sequense */
      }
      pb->bs[++pb->wi] = (byte)c; /* Save the trailing byte */
      if (--pb->ct == 0) break;   /* End of the sequence? */
      return;
    }
  }
  tp = (const TCHAR *)pb->bs;
  dc = tchar2uni(&tp);          /* UTF-8 ==> UTF-16 */
  if (dc == 0xFFFFFFFF) return; /* Wrong code? */
  hs = (char16_t)(dc >> 16);
  wc = (char16_t)dc;
#      elif FF_LFN_UNICODE == 3 /* UTF-32 input */
  if (IsSurrogate(c) || c >= 0x110000) return;    /* Discard invalid code */
  if (c >= 0x10000) {                             /* Out of BMP? */
    hs = (char16_t)(0xD800 | ((c >> 10) - 0x40)); /* Make high surrogate */
    wc = 0xDC00 | (c & 0x3FF);                    /* Make low surrogate */
  } else {
    hs = 0;
    wc = (char16_t)c;
  }
#      endif
  /* A code point in UTF-16 is available in hs and wc */

#      if FF_STRF_ENCODE == 1 /* Write a code point in UTF-16LE */
  if (hs != 0) {              /* Surrogate pair? */
    st_word(&pb->buf[i], hs);
    i += 2;
    nc++;
  }
  st_word(&pb->buf[i], wc);
  i += 2;
#      elif FF_STRF_ENCODE == 2 /* Write a code point in UTF-16BE */
  if (hs != 0) { /* Surrogate pair? */
    pb->buf[i++] = (byte)(hs >> 8);
    pb->buf[i++] = (byte)hs;
    nc++;
  }
  pb->buf[i++] = (byte)(wc >> 8);
  pb->buf[i++] = (byte)wc;
#      elif FF_STRF_ENCODE == 3 /* Write a code point in UTF-8 */
  if (hs != 0) { /* 4-byte sequence? */
    nc           += 3;
    hs            = (hs & 0x3FF) + 0x40;
    pb->buf[i++]  = (byte)(0xF0 | hs >> 8);
    pb->buf[i++]  = (byte)(0x80 | (hs >> 2 & 0x3F));
    pb->buf[i++]  = (byte)(0x80 | (hs & 3) << 4 | (wc >> 6 & 0x0F));
    pb->buf[i++]  = (byte)(0x80 | (wc & 0x3F));
  } else {
    if (wc < 0x80) { /* Single byte? */
      pb->buf[i++] = (byte)wc;
    } else {
      if (wc < 0x800) { /* 2-byte sequence? */
        nc           += 1;
        pb->buf[i++]  = (byte)(0xC0 | wc >> 6);
      } else { /* 3-byte sequence */
        nc           += 2;
        pb->buf[i++]  = (byte)(0xE0 | wc >> 12);
        pb->buf[i++]  = (byte)(0x80 | (wc >> 6 & 0x3F));
      }
      pb->buf[i++] = (byte)(0x80 | (wc & 0x3F));
    }
  }
#      else                     /* Write a code point in ANSI/OEM */
  if (hs != 0) return;
  wc = ff_uni2oem(wc, CODEPAGE); /* UTF-16 ==> ANSI/OEM */
  if (wc == 0) return;
  if (wc >= 0x100) {
    pb->buf[i++] = (byte)(wc >> 8);
    nc++;
  }
  pb->buf[i++] = (byte)wc;
#      endif

#    else /* ANSI/OEM input (without re-encoding) */
  pb->buf[i++] = (byte)c;
#    endif

  if (i >= (int)(sizeof pb->buf) - 4) { /* Write buffered characters to the file */
    f_write(pb->fp, pb->buf, (uint)i, &n);
    i = (n == (uint)i) ? 0 : -1;
  }
  pb->idx  = i;
  pb->nchr = nc + 1;
}

/* Flush remaining characters in the buffer */

static int putc_flush(putbuff *pb) {
  uint nw;

  if (pb->idx >= 0 /* Flush buffered characters to the file */
      && f_write(pb->fp, pb->buf, (uint)pb->idx, &nw) == FR_OK && (uint)pb->idx == nw)
    return pb->nchr;
  return -1;
}

/* Initialize write buffer */

static void putc_init(putbuff *pb, FIL *fp) {
  memset(pb, 0, sizeof(putbuff));
  pb->fp = fp;
}

int f_putc(TCHAR c, /* A character to be output */
           FIL  *fp /* Pointer to the file object */
) {
  putbuff pb;

  putc_init(&pb, fp);
  putc_bfd(&pb, c); /* Put the character */
  return putc_flush(&pb);
}

/*-----------------------------------------------------------------------*/
/* Put a String to the File                                              */
/*-----------------------------------------------------------------------*/

int f_puts(const TCHAR *str, /* Pointer to the string to be output */
           FIL         *fp   /* Pointer to the file object */
) {
  putbuff pb;

  putc_init(&pb, fp);
  while (*str)
    putc_bfd(&pb, *str++); /* Put the string */
  return putc_flush(&pb);
}

/*-----------------------------------------------------------------------*/
/* Put a Formatted String to the File (with sub-functions)               */
/*-----------------------------------------------------------------------*/
#    if FF_PRINT_FLOAT && FF_INTDEF == 2
#      include <math.h>

static int ilog10(double n) /* Calculate log10(n) in integer output */
{
  int rv = 0;

  while (n >= 10) { /* Decimate digit in right shift */
    if (n >= 100000) {
      n  /= 100000;
      rv += 5;
    } else {
      n /= 10;
      rv++;
    }
  }
  while (n < 1) { /* Decimate digit in left shift */
    if (n < 0.00001) {
      n  *= 100000;
      rv -= 5;
    } else {
      n *= 10;
      rv--;
    }
  }
  return rv;
}

static double i10x(int n) /* Calculate 10^n in integer input */
{
  double rv = 1;

  while (n > 0) { /* Left shift */
    if (n >= 5) {
      rv *= 100000;
      n  -= 5;
    } else {
      rv *= 10;
      n--;
    }
  }
  while (n < 0) { /* Right shift */
    if (n <= -5) {
      rv /= 100000;
      n  += 5;
    } else {
      rv /= 10;
      n++;
    }
  }
  return rv;
}

static void ftoa(char  *buf,  /* Buffer to output the floating point string */
                 double val,  /* Value to output */
                 int    prec, /* Number of fractional digits */
                 TCHAR  fmt   /* Notation */
) {
  int         d;
  int         e = 0, m = 0;
  char        sign = 0;
  double      w;
  const char *er = 0;
  const char  ds = FF_PRINT_FLOAT == 2 ? ',' : '.';

  if (isnan(val)) { /* Not a number? */
    er = "NaN";
  } else {
    if (prec < 0) prec = 6; /* Default precision? (6 fractional digits) */
    if (val < 0) {          /* Negative? */
      val  = 0 - val;
      sign = '-';
    } else {
      sign = '+';
    }
    if (isinf(val)) { /* Infinite? */
      er = "INF";
    } else {
      if (fmt == 'f') {            /* Decimal notation? */
        val += i10x(0 - prec) / 2; /* Round (nearest) */
        m    = ilog10(val);
        if (m < 0) m = 0;
        if (m + prec + 3 >= SZ_NUM_BUF) er = "OV"; /* Buffer overflow? */
      } else {                                     /* E notation */
        if (val != 0) {                            /* Not a true zero? */
          val += i10x(ilog10(val) - prec) / 2;     /* Round (nearest) */
          e    = ilog10(val);
          if (e > 99 || prec + 7 >= SZ_NUM_BUF) { /* Buffer overflow or E > +99? */
            er = "OV";
          } else {
            if (e < -99) e = -99;
            val /= i10x(e); /* Normalize */
          }
        }
      }
    }
    if (!er) {                        /* Not error condition */
      if (sign == '-') *buf++ = sign; /* Add a - if negative value */
      do {                            /* Put decimal number */
        if (m == -1) *buf++ = ds;     /* Insert a decimal separator when get into fractional part */
        w       = i10x(m);            /* Snip the highest digit d */
        d       = (int)(val / w);
        val    -= d * w;
        *buf++  = (char)('0' + d); /* Put the digit */
      } while (--m >= -prec);      /* Output all digits specified by prec */
      if (fmt != 'f') {            /* Put exponent if needed */
        *buf++ = (char)fmt;
        if (e < 0) {
          e      = 0 - e;
          *buf++ = '-';
        } else {
          *buf++ = '+';
        }
        *buf++ = (char)('0' + e / 10);
        *buf++ = (char)('0' + e % 10);
      }
    }
  }
  if (er) {                  /* Error condition */
    if (sign) *buf++ = sign; /* Add sign if needed */
    do {                     /* Put error symbol */
      *buf++ = *er++;
    } while (*er);
  }
  *buf = 0; /* Term */
}
#    endif /* FF_PRINT_FLOAT && FF_INTDEF == 2 */

int f_printf(FIL         *fp,  /* Pointer to the file object */
             const TCHAR *fmt, /* Pointer to the format string */
             ...               /* Optional arguments... */
) {
  va_list arp;
  putbuff pb;
  uint    i, j, w, f, r;
  int     prec;
#    if FF_PRINT_LLI && FF_INTDEF == 2
  u64 v;
#    else
  u32 v;
#    endif
  TCHAR *tp;
  TCHAR  tc, pad;
  TCHAR  nul = 0;
  char   d, str[SZ_NUM_BUF];

  putc_init(&pb, fp);

  va_start(arp, fmt);

  for (;;) {
    tc = *fmt++;
    if (tc == 0) break; /* End of format string */
    if (tc != '%') {    /* Not an escape character (pass-through) */
      putc_bfd(&pb, tc);
      continue;
    }
    f = w = 0;
    pad   = ' ';
    prec  = -1; /* Initialize parms */
    tc    = *fmt++;
    if (tc == '0') { /* Flag: '0' padded */
      pad = '0';
      tc  = *fmt++;
    } else if (tc == '-') { /* Flag: Left aligned */
      f  = 2;
      tc = *fmt++;
    }
    if (tc == '*') { /* Minimum width from an argument */
      w  = va_arg(arp, int);
      tc = *fmt++;
    } else {
      while (IsDigit(tc)) { /* Minimum width */
        w  = w * 10 + tc - '0';
        tc = *fmt++;
      }
    }
    if (tc == '.') { /* Precision */
      tc = *fmt++;
      if (tc == '*') { /* Precision from an argument */
        prec = va_arg(arp, int);
        tc   = *fmt++;
      } else {
        prec = 0;
        while (IsDigit(tc)) { /* Precision */
          prec = prec * 10 + tc - '0';
          tc   = *fmt++;
        }
      }
    }
    if (tc == 'l') { /* Size: long int */
      f  |= 4;
      tc  = *fmt++;
#    if FF_PRINT_LLI && FF_INTDEF == 2
      if (tc == 'l') { /* Size: long long int */
        f  |= 8;
        tc  = *fmt++;
      }
#    endif
    }
    if (tc == 0) break; /* End of format string */
    switch (tc) {       /* Atgument type is... */
    case 'b': /* Unsigned binary */ r = 2; break;

    case 'o': /* Unsigned octal */ r = 8; break;

    case 'd': /* Signed decimal */
    case 'u': /* Unsigned decimal */ r = 10; break;

    case 'x': /* Unsigned hexadecimal (lower case) */
    case 'X': /* Unsigned hexadecimal (upper case) */ r = 16; break;

    case 'c': /* Character */ putc_bfd(&pb, (TCHAR)va_arg(arp, int)); continue;

    case 's':                    /* String */
      tp = va_arg(arp, TCHAR *); /* Get a pointer argument */
      if (!tp) tp = &nul;        /* Null ptr generates a null string */
      for (j = 0; tp[j]; j++)
        ;                                        /* j = tcslen(tp) */
      if (prec >= 0 && j > (uint)prec) j = prec; /* Limited length of string body */
      for (; !(f & 2) && j < w; j++)
        putc_bfd(&pb, pad); /* Left pads */
      while (*tp && prec--)
        putc_bfd(&pb, *tp++); /* Body */
      while (j++ < w)
        putc_bfd(&pb, ' '); /* Right pads */
      continue;
#    if FF_PRINT_FLOAT && FF_INTDEF == 2
    case 'f':                                   /* Floating point (decimal) */
    case 'e':                                   /* Floating point (e) */
    case 'E':                                   /* Floating point (E) */
      ftoa(str, va_arg(arp, double), prec, tc); /* Make a floating point string */
      for (j = strlen(str); !(f & 2) && j < w; j++)
        putc_bfd(&pb, pad); /* Left pads */
      for (i = 0; str[i]; putc_bfd(&pb, str[i++]))
        ; /* Body */
      while (j++ < w)
        putc_bfd(&pb, ' '); /* Right pads */
      continue;
#    endif
    default: /* Unknown type (pass-through) */ putc_bfd(&pb, tc); continue;
    }

    /* Get an integer argument and put it in numeral */
#    if FF_PRINT_LLI && FF_INTDEF == 2
    if (f & 8) { /* long long argument? */
      v = (u64)va_arg(arp, long long);
    } else if (f & 4) { /* long argument? */
      v = (tc == 'd') ? (u64)(long long)va_arg(arp, long) : (u64)va_arg(arp, unsigned long);
    } else { /* int/short/char argument */
      v = (tc == 'd') ? (u64)(long long)va_arg(arp, int) : (u64)va_arg(arp, unsigned int);
    }
    if (tc == 'd' && (v & 0x8000000000000000)) { /* Negative value? */
      v  = 0 - v;
      f |= 1;
    }
#    else
    if (f & 4) { /* long argument? */
      v = (u32)va_arg(arp, long);
    } else { /* int/short/char argument */
      v = (tc == 'd') ? (u32)(long)va_arg(arp, int) : (u32)va_arg(arp, unsigned int);
    }
    if (tc == 'd' && (v & 0x80000000)) { /* Negative value? */
      v  = 0 - v;
      f |= 1;
    }
#    endif
    i = 0;
    do { /* Make an integer number string */
      d  = (char)(v % r);
      v /= r;
      if (d > 9) d += (tc == 'x') ? 0x27 : 0x07;
      str[i++] = d + '0';
    } while (v && i < SZ_NUM_BUF);
    if (f & 1) str[i++] = '-'; /* Sign */
    /* Write it */
    for (j = i; !(f & 2) && j < w; j++) { /* Left pads */
      putc_bfd(&pb, pad);
    }
    do { /* Body */
      putc_bfd(&pb, (TCHAR)str[--i]);
    } while (i);
    while (j++ < w) { /* Right pads */
      putc_bfd(&pb, ' ');
    }
  }

  va_end(arp);

  return putc_flush(&pb);
}

#  endif /* !FF_FS_READONLY */
#endif   /* FF_USE_STRFUNC */

#if FF_CODE_PAGE == 0
/*-----------------------------------------------------------------------*/
/* Set Active Codepage for the Path Name                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_setcp(u16 cp /* Value to be set as active code page */
) {
  static const u16         validcp[22] = {437, 720, 737, 771, 775, 850, 852, 855, 857, 860, 861,
                                          862, 863, 864, 865, 866, 869, 932, 936, 949, 950, 0};
  static const byte *const tables[22]  = {Ct437, Ct720, Ct737, Ct771, Ct775, Ct850, Ct852, Ct855,
                                          Ct857, Ct860, Ct861, Ct862, Ct863, Ct864, Ct865, Ct866,
                                          Ct869, Dc932, Dc936, Dc949, Dc950, 0};
  uint                     i;

  for (i = 0; validcp[i] != 0 && validcp[i] != cp; i++)
    ;                                                /* Find the code page */
  if (validcp[i] != cp) return FR_INVALID_PARAMETER; /* Not found? */

  CodePage = cp;
  if (cp >= 900) { /* DBCS */
    ExCvt  = 0;
    DbcTbl = tables[i];
  } else { /* SBCS */
    ExCvt  = tables[i];
    DbcTbl = 0;
  }
  return FR_OK;
}
#endif /* FF_CODE_PAGE == 0 */
